Raju

CBSE Sample Papers for Class 12 Computer Science Paper 4 are part of CBSE Sample Papers for Class 12 Computer Science. Here we have given CBSE Sample Papers for Class 12 Computer Science Paper 4.

CBSE Sample Papers for Class 12 Computer Science Paper 4

Students who are going to appear for CBSE Class 12 Examinations are advised to practice the CBSE sample papers given here which is designed as per the latest Syllabus and marking scheme, as prescribed by the CBSE, is given here. Paper 4 of Solved CBSE Sample Paper for Class 12 Maths is given below with free PDF download Answers.

Time: 3 Hours
Maximum Marks: 70

General Instructions:

• All questions are compulsory within each Section.
• Programming Language in SECTION A : C++.
• Answer the questions after carefully reading the text.

SECTION A

Question 1.
(a) Find out the correct identifiers out of the following, which can be used for naming variables, constants or functions in a C++ program.

File-Rec, 2abc, _DSP, D.9_7, My_2_3_90, if, getch, For, totalNum

(b) Meenu has started learning C++ and has typed the following program. When she compiled the following code written by her, she discovered that see needs to include some header files to successfully compile and execute it. Write the name of those header files, which are required to be included in the code.

void main()
{
char C, String[] = "Exercise Question1";
for(int i=0; String[i]!='\0'; i++)
if(isdigit(String[i])!= 0)
cout< else
cout<<String[i];
}

(c) Observe the following C++ code carefully and rewrite the same after removing all the syntax error(s) present in the code. Ensure that you 5 underline each correction in the code.
Note: Assume all the desired header files are already being included, which are required to run the code.
Correction should not change the logic of the program.

void main()
{
Future=55, Past=45;
Assign(Future; Past);
Assign(Past);
}
void Assign(int Default1, Default2=50)
{
Default1 = Default1+Default2;
cout<>Default2;
}

(d) Give the output of the following program code:
Note: Assume all required header files are already being included.

void displaylchar *S)
{
for(int a=0; S[a]>0; a++)
{
for(int Y=0; Y<=a; Y++)
cout<<S[Y];
cout<<endl;
}
}
void main()
{
char *t = "DARK";
display(t);
}

(e) Find and write the output of the following program code:
Note: Assume all required header files are already being included in the program.

class String
{
char Text[];
int Count;
public:
void Change(char Text[],int &Count)
{
char *Ptr = Text;
int len = strlen(Text);
for(;Count<len-2; Count+=2, Ptr++)
{
*(Ptr+Count) = tolower(*(Ptr+Count));
}
}
};
void main()
{
clrscr();
String S;
int Position = 1;
char Message!!] = "POINTERS MAGIC";
S.Change(Message,Position);
cout<<Message<<"@"<<Position; 
}

(f) Observe the following program and find out, which output(s) out of (i) to (iv) will be expected from the program? Also, find out the minimum and the maximum value that can be assigned to the variable Points used in the code. Note: Assume all required header files are already being included in the program. random(n) function generates an integer between 0 to n-1

const int LIMIT = 4; 
void main() 
{ 
randomize(); 
int Points; 
Points = 100 + random(LIMIT); 
for(int P=Points; P>=100; P--)
cout<<P<<"#";
}

(i) 100#101#102#103#104
(ii) 103#102#101#100#
(iii) 100#101#102#103
(iv) 104#101#102#103#

Question 2.
(a) Define the term of Inheritance. Give an example in C++ to illustrate it.
(b) Answer the following questions (i) and (ii) after going through the following class:

class Science
{
char Topic[20];
int Weightage;
public:
Science() // Function1
{
strcpy(Topic,"Optics");
Weightage = 30;
cout<<"Topic Activated":
}
~Science() // Function2
{
cout<<"Topic Deactivated":
}
};

(i) Name the specific features of class shown by Function1 and Function2 in the above example.
(ii) How would Function1 and Function2 get executed?
(c) Define a class Cricket in C+ + with the following description:
Private members

• Target_score of type integer
• Overs bowled of type integer
• Extra time of type integer
• A penalty of type integer
• Cal_Penalty()
  a member function to calculate penalty as follows:

if Extra_time<=10, Penalty=1 if Extra_time>10 but<=20, Fenalty=2 otherwise, Penalty=5

Public members

• A function Enterdata() to allow user to enter values for Target_score, Overs_bowled, Extra_time. Also, this function should call Cal_Penalty() to calculate penalty.
• A function Dispdata() to allow user to view the contents of all data members.

(d) Consider the following code and answer the questions given below:

class CHead
{
double Turnover:
protected:
int noofcomp;
public:
CHead();
void INPUT(int);
void OUTPUT();
};
class Director:public CHead
{
int noofemp;
protected:
float funds:
public:
Director();
void INDATA();
void OUTDATA();
};
class Manager: public Director
{
float Expense;
public;
Manager();
void DISPLAY(void);
};

(i) Which type of Inheritance out of the following is illustrated in the above example?
I. Single Level Inheritance
II. Multi Level Inheritance
III. Multiple Inheritance
(ii) How many bytes will an object belonging to class Manager required?
(iii) Name the member function(s), which are directly accessible from the object of class Manager.
(iv) Is the member function OUTPUT() accessible by the object of the class Director?

Question 3.
(a) Write a function check () to check, if the passed array of integers is sorted or not. The function should return 1 if arranged in ascending order, -1 if arranged in descending order, 0 if it is not sorted.
(b) An array S[30][20] is stored in the memory along the row with each of the elements occupying 4 bytes. Find out the base address, if an element S[15] [10] is stored at the memory location 7200.
(c) Each node of a STACK contains the following information, in addition pointer field
(i) Pincode of city
(ii) Name of city
Give the structure of node for the linked STACK in question. TOP is a pointer that points to the topmost node of the STACK.
To remove a node from the STACK, which is dynamically allocated STACK of items considering the following code is already written as a part of the program.

struct node
{
int Pincode;
char city[15];
node *link;
};
class STACK
{
node *T0P;
public:
STACK()
{
TOP=NULL;
}
void PUSH();
void POP();
STACK();
};

(d) Evaluate the following postfix expression using a stack. Show the contents of stack after execution of each operation.
20, 8, 4, /, 2, 3, + , *, –
(e) Write a function in C++ to find sum of rows from a two dimensional array.
e.g. if two dimensional array contains
8 7 2
5 1 0
4 8 3
Output
Sum of row 1 is : 17
Sum of row 2 is : 6
Sum of row 3 is : 15

Question 4.
(a) Find the output of the following C++ code considering that the binary file “School.dat” exists on the hard disk with a data of 100 members.

#include
#include
#include
class School
{
int Scode;
char Name[25];
public:
void Input();
void Output();
};
void main()
{
ifstream f:
f.open("School.dat", ios::binary | ios :: in);
School S;
f.read!(char*)&S, sizeof(S));
f.read!(char*)&S, sizeof(S));
int POS=f.tellg()/sizeof (S);
cout<<"\nPresent Record:"<<POS<<endl; 
f.close(); 
getch(); 
}

(b) Write a function in C++ to count the number of alphabets present in a text file “STORY. TXT”. e.g. If the file contains Computer science is the scientific and practical approach to computation and its application. It is the systematic study of the feasibility, structure, expression and mechanization of the methodical procedures. The number of alphabets: 179
(c) Assuming the class Computer as follows:

class Computer 
{ char chiptype[10]; 
int Speed; 
public: 
void getdetails() 
{ 
gets(chiptype); 
cin>>Speed;
}
void showdetails()
{
cout<<"Chip"<<chiptype<<"Speed="<<Speed;
}
};

Write a function readfile() to read all the records present in an already existing binary file “COMP.DAT” and display them on the screen, also count the number of records present in the file.

SECTION B

Question 5.
(a) Observe the following tables Employee and Manager carefully and write the name of the RDBMS operation which will be used to produce the output as shown in “Output”. Also, find the degree and cardinality of the “Output”.

(b) Write SQL queries for (i) to (iv) and find outputs for queries (v) to (viii) on the basis of the tables MOBILE and VENDOR

(i) To display the names of all Samsung mobile users.
(ii) To display customer name and amount of all those mobiles whose amount is more than 800.
(iii) To display the number of users for each connection, i.e. the expected output should be
101 2
102 3
103 2
104 2
105 1
(iv) To display Cname, Model and Validity in decreasing order of Validity.

(v) SELECT COUNT(DISTINCT Model) FROM MOBILE;
(vi) SELECT MAX(Activation), MIN(Activation) FROM MOBILE;
(vii) SELECT A.Connection, B.Cname, B.Amount FROM VENDOR A,MOBILE B
WHERE A.CCode=B.CCode AND Cname LIKE 'r%'
(viii) SELECT Benefits, Cname, Activation FROM VENDOR, MOBILE
WHERE VENDOR.CCode=MOBILE.Ccode
AND Activation BETWEEN '2004-05-14' AND '2004-06-10';

Question 6.
(a) Verify the following algebraically:
\(\left( \bar { A } +\bar { B } \right) \cdot \left( A+B \right) =\bar { A } \cdot B+A\cdot \bar { B }\)
(b) Write the Boolean expression for the result of the logic circuit as shown below:

(c) Write the canonical SOP form of a Boolean function F, which is represented in a truth table as follows:

(d) Reduce the following Boolean expression using K-map
F(u, v, w, z) = Π (0, 1, 2, 4, 5, 6, 8, 10)

Question 7.
(a) How does CDMA technique works?
(b) Anuradha is a Web developer. She has designed a login form to input the login id and password of the user. She has to write a script to check whether the login id and the corresponding password as entered by the user are correct or not. What kind of script from the following will be most suitable for doing the same?
(i) JSP
(ii) Client-Side Script
(iii) VB Script
(c) How is wi-fi different from wi-max?
(d) What do you mean by IP address? How is it useful in computer security?
(e) Computer Ltd has set-up its new center at Meerut for its office and Web-based activities. It has 4 blocks of buildings as shown in the diagram below:

(i) Suggest a cable layout of connections between the blocks.
(ii) Suggest the most suitable place (i.e. block) to house the server. Give reason also.
(iii) Suggest the placement of repeater device with justification.
(iv) The organization is planning to link its front office situated in the city in a hilly region where the cable connection is not feasible, suggest an economical way to connect it with reasonably high speed.
(f) list any two disadvantages of the star topology.
(g) How is a hacker different from a cracker?

Answers

Answer 1.
(a) Correct identifiers are: _DSP, My_2_3_90, For, totalNum

(b) → cout()
→ isdigit()
(c) The correct code is:
void Assian(int Default1. int Default2=50):
void main()
{
int Future=55, Past=45;
Assiqn(Future, Past):
Assign(Past);
}
void Assign(int Default1, int Default2)
{
Default1=Default1+Default2;
cout<<Default1<<Default2:
}

(d) Output
D
DA
DAR
DARK
(e) Output
PoINtERs MaGIc@13
(f) Possible output is
(ii) 103#102#101#100#
The minimum value of variable Points = 100
The maximum value of variable Points = 103

Answer 2.
(a) Inheritance is the capability to inherit the properties from another class. The class that derives its properties is called derived class or child class and the class from which the properties are derived is called the base class or parent class. The child class can access all properties and behaviors, the child class along with the inherited properties can possess its own properties. In other words, inheritance is a way of code reusability.
Inheritance can be done by using the following syntax:

class : 
{
..........
.........
};

The following program illustrates the use of inheritance:
e.g.

#include
#include
class Parent
{
public;
int num;
void fun()
{
num=10;
cout<<num;
}
};
class Child:public Parent
{
void fun1()
{
num = 20;
cout<<num;
}
};
void main()
{
Child obj;
//child class object calling base class function
obj.fun();
}

(b) (i) Specific features of class shown by Function 1 is the constructor and by Function2 is destructor.
(ii) Whenever an object of class Science is created, Function1 will be called automatically, similarly, Function2 will be invoked automatically whenever Science class object goes out of scope.

(c) class Cricket
{
private:
int Target_score;
int Overs_bowled;
int Extra_time;
int Penalty;
void Cal_Penalty()
{
if(Extra_time <= 10)
Penalty = 1;
else if(Extra_time <= 20)
Penalty = 2;
else
Penalty = 5;
}
public:
void Enterdata()
{
cout<<"Enter Target Score\n"; cin>>Target_score;
cout<<"\nEnter overs bowled": cin>>Overs_bowled;
cout<<"\nEnter Extra Time"; cin>>Extra_time;
Cal_Penalty();
}
void Dispdata()
{
cout<<"Target Score:"<<Target_score;
cout<<"\nOvers bowled:"<<0vers_bowled;
cout<<"\nExtra Time:"<<Extra_time;
cout<<"Penalty:"<<Penalty; 
} 
};

(d) (i) II. Multi Level Inheritance
(ii) Object belonging to class Manager will require 20 bytes.
(iii) The member functions which are directly accessible from the object of class Manager are as follows: DISPLAY(), INDATA(), OUTDATA(), INPUT(), OUTPUT()
(iv) Yes, the member function OUTPUT() is directly accessible by the object of class Director.

Answer 3.

(a) int check(int a[], int n) { int f=0, i = 0; if(a[i]>a[i+1])
{
f=-1;
for(i = 1; i<n-1; i++)
{
if(a[i ]<a[i +1])
{
f=0;
break;
}
}
}
el se
{
f = 1;
for(int i=1; i< n-1; i++) { if(a[i]>a[i+1])
{
f =0;
break;
}
}
}
return f;
}

(b) M= 30, N= 20 and W = 4 bytes
So, address of
S[15][10] = Base + [N*(I-0)+(J-0)] *W
7200 = Base + [20*(15 – 0) + (10 – 0)]* 4
7200 = Base + [300+10]* 4
7200 = Base + [310]* 4
7200 = Base + 1240
Base = 7200 – 1240
Base = 5960

(c) void POP(node *T0P; int Pin, char Mcity[])
{
node *temp;
char Mcity[15];
if(TOP==NULL)
cout<<"\nError!!Stack is Empty!!"; else { temp = TOP; TOP = TOP—> link;
Pin = temp->Pincode;
strcpy(Mcity, temp->City);
delete temp;
}
return(TOP);

(d) The postfix expression 20, 8, 4, /, 2, 3, +, *, –

Result = 10

(e) void sumrow(int A[][4], int n, int m)
{
for(int p=0; p<n; p++)
{
int sum = 0;
for(int q=0; q<m; q++)
sum+= A[p][q];
cout<<"Sum of row "<<p+1<<" is: "<<sum;
}
}

Answer 4.
(a) Present Record : 2

(b) void Count()
{
ifstream fin("STORY.TXT", ios::in);
int n=0;
char ch = fin.get();
while(!fin.eof())
{
if(isalpha(ch))
n++;
ch = fin.get();
}
cout<<"Number of alphabets:"<<n<<endl;
}
(c) void Computer::Readfile()
{
int i=0;
ifstream file;
fi1e.open("COMP.DAT", ios::binary | ios::in);
Computer c;
while(file.read((char*)&c, sizecrf(c)))
{
c.showdetais();
i = i+1;
}
cout<<"Number of records present"<<i; 
file.close(); 
}

Answer 5.
(a) RDBMS operation is Intersection Degree = 2 Cardinality = 3

(b) (i) SELECT Cname FROM MOBILE WHERE Model = 'Samsung'; 
(ii) SELECT Cname. Amount FROM MOBILE WHERE Amount > 800;
(iii) SELECT CCode, COUNT(Cname) FROM MOBILE GROUP BY CCode;
(iv) SELECT Cname, Model. Validity FROM MOBILE ORDER BY Validity DESC;

Answer 6.

Answer 7.
(a) In the CDMA technique, the data is sent in small pieces over a number of discrete frequencies available for use at any time in the specified range.
(b) (i) JSP, as server-side scripting will be used.
(c) Differences between wi-fi and wi-max are as follows:

(d) An Internet Protocol (IP) address is a numerical identification and logical address that is assigned to devices connected in a computer network.
In a network, every machine can be identified by a unique IP address associated with it and thus, help in providing network security to every system connected in a network.
(e) (i) Cable layout

(ii) The most suitable place to house the server is Block C as this block contains the maximum number of computers.
(iii) Since the distance between Block A and Block C is larger, so a repeater would ideally be placed in between this path.

(iv) The most economical way to connect it with a reasonably high speed would be to use radio waves transmission as it is easy to install as compared to other unguided media, can travel long distances and penetrate walls.
(f) Two disadvantages of star topology are as follows:
(i) It is difficult to expand.
(ii) If the central node of the network fails, the entire network is rendered inoperable.
(g) The crackers are malicious programmers who break into secure systems whereas hackers are more interested in gaining knowledge about computer systems and possibly using this knowledge for playful pranks.

We hope the CBSE Sample Papers for Class 12 Computer Science Paper 4 help you. If you have any query regarding CBSE Sample Papers for Class 12 Computer Science Paper 4, drop a comment below and we will get back to you at the earliest.

CBSE Sample Papers for Class 12 Computer Science Paper 3 are part of CBSE Sample Papers for Class 12 Computer Science. Here we have given CBSE Sample Papers for Class 12 Computer Science Paper 3.

CBSE Sample Papers for Class 12 Computer Science Paper 3

Students who are going to appear for CBSE Class 12 Examinations are advised to practice the CBSE sample papers given here which is designed as per the latest Syllabus and marking scheme, as prescribed by the CBSE, is given here. Paper 3 of Solved CBSE Sample Paper for Class 12 Computer Science is given below with free PDF download Answers.

Time: 3 Hours
Maximum Marks: 70

General Instructions:

• All questions are compulsory within each Section.
• Programming Language in SECTION A : C++.
• Answer the questions after carefully reading the text.

SECTION A

Question 1.
(a) Out of the following find those identifiers, which can be used for naming variable, constant or function in a C++ program:
throw, Num2, sum^3, THIS, Float, return, _Sum, first name
(b) Which C++ header file(s) will be essentially required to be included to run/execute the following C++ code?

void main()
{
char Info[]="Indian Army";
for(int I=5; I<strlen(Info): I++)
puts(Info):
}

(c) Rewrite the following program after removing the syntactical error(s) (if any). Underline each correction.
Note: Assume all required header files are already being included in the program.

Main()
{
Float x, y, z;
cout<<"Enter two numbers": cin>>a>>b
cout<<"The numbers in reverse order are"<<b, a;
}

(d) Find and write the output of the following program:
Note: Assume all required header files are already being included in the program.

struct Play
{
char Arr[20];
int n;
};
void main()
{
Play P = {"Magic",500};
P.Arr[4] = 'Q';
P.Arr[2] = 'L' ;
P.n+= 50;
cout<<P.Arr<<P.n<<endl;
Play R = P;
R.n- = 120;
cout<<R.n<<endl;
}

(e) Observe the following C+ + code carefully and obtain the output, which will appear on the screen after the execution of it.
Note: Assume all required header files are already being included in the program.

class Array
{
int num;
int size:
public:
void Change(int num, int arr[], int size)
{
for(int n=0; n<size; n++)
if (n<num)
arr[n]+ = n;
else
arr[n] * = n;
}
void display(int arr[], int size)
{
for(int n=0; n<size; n++)
(n%2!=0)? cout<<arr[n]<<"#":cout<<arr[n]<<endl:
}
};
void main()
{
clrscr();
Array a:
int array[] = {50,40,90,10,60,70};
a.Change(4, array, 7);
a.display(array, 7);
getch();
}

(f) The following code is from a game, which generates a set of 4 random numbers. Ravi is playing this game, help him to identify the correct option(s) out of the four choices given below as the possible set of such numbers generated from the program code so that he wins the game. Also, find out the minimum and maximum value that can be assigned to the variable Number used in the code at the time when the value of I is 2.
Note:
Assume all required header files are already being included in the program.
random(n) function generates an integer between 0 and n-1

const int a = 15;
void main()
{
randomize();
int POINT = 5, Number;
for(int I=1; I<=4; I++)
{
Number = a+random(POINT);
cout<<Number<<":";
POINT--;
}
}

(i) 19: 16 : 15: 18 :
(ii) 14: 18: 15: 16 :
(iii) 19: 16 : 14: 18 :
(iv) 19: 16: 15: 16 :

Question 2.
(a) What do you understand by polymorphism? Give a suitable example.
(b) Answer the questions (i) and (ii) after going through the following program:

class Student
{
int stuID;
char address[50];
float fees;
public:
Student() //Function1
{
stuID=108;
strcpy(address,"MEERUT");
fees=5400;
}
void Course(float C) //Function2
{
cout<<stuID<<":"<<address<<":”<<fees<<endl;
}
~Student() //Function3
{
cout<<"Course Cancelled"< }
Student(int S, char A[], float C) //Function4
{
stuID=S;
strcpy(address. A):
fees=C;
}
};
void main() //Line1
{ //Line2
Student S1, S2(102, "Meerut", 20); //Line3
for(int i=0; i<5; i++) //Line4
{ //Line5
S1 .Course(50); //Line6
S2.Course(45); / / Line7
} //Line8
} //Line9

(i) In object-oriented programming, what are Function1 and Function4 combined together as?
(ii) How many times the message “Course Cancelled” will be displayed after executing the above C++ code? Out of Line1 to Line9, which line is responsible to display the message “Course Cancelled”?
(c) Define a class Batsman with the following specifications:
Private members
bcode – 4 digit code (maybe number and character)
bname – 20 characters
innings, not out, runs – integer type
batavg – It is calculated according to the formula batavg= runs/(innings-not out)
calcavg() – Function to compute batavg
Public members
readdata() – Function to accept values of bcode, bname, innings, not out and invoke the function calcavg()
displaydata() – Function to display the data members on the screen.
(d) Answer the questions (i) to (iv) based on the following code:

class Shape
{
int length;
protected:
int width, height;
public:
void getDimension(int, int, int);
void dispDimension();
};
class SideShape:protected Shape
{
int SideLength, SideWidth;
protected:
void getSide(int, int);
public:
void dispSide();
};
class SubShape:public SideShape
{
int SubLength;
void display(void);
public:
void enter();
};

(i) Name of the base class and derived class of the class SlideShare.
(ii) Name of the data member(s) that can be accessed from function dispSide().
(iii) Name of the private member function(s) of class subshape.
(iv) Which type of inheritance is illustrated in the above example?

Question 3.
(a) Write a code for a function Change (int a[ ], int size) in C++, to add 8 in all the odd values and 6 in all the even values of the array a.
e.g. If the array a is:
8, 7, 5, 4, 5, 2, 6
The output will be:
14, 15, 13, 10, 13, 8, 12
(b) An array X [10] [20] is stored in memory with each element requiring 4 bytes of storage. If the base address of the array is 1000, calculate the location of X [5] [15] when the array X is stored using column-major order.
(c) Write a function in C++ which accepts an integer array and its size as an argument and assign the elements in the 2-D array in the following format:
e.g. If the 1-D array is: 1, 2, 3, 4
The resultant 2-D array should be

e.g. If the 1-D array is: 1, 2, 3
The resultant 2-D array should be

(d) Evaluate the following postfix notation of expression
True, False, AND, True, True, NOT, OR, AND
(e) Each node of a stack contains the following information, in addition to pointer field
(i) EmpCode of employee
(ii) EName of employee
Give the structure of node for the linked stack in question. Top is a pointer that points to the topmost node of the stack. To push a node into the stack, which is dynamically allocated stack of items considering the following code is already written as a part of the program.

struct node
{
int EmpCode;
char Ename[15];
node * link;
};
class Stack
{
node * Top;
public:
Stack()
{
Top=NULL;
}
void PUSH();
void POP();
~Stack();
};

Question 4.
(a) Observe the following code and answer the following question:

void main()
{
char ch = 'z';
fstream fileout("data.dat",ios::app);
fileout<<ch;
int p=fileout.tellg();
cout<<p;
}

What is the output if the file content before the execution of the program is the string “ARIHANT”?
Note: ” ” are not part of the file.
(b) Write a function COUNT_HOW() in C++ to count the presence of the word “How” in a text file “MEMO.TXT”.
e.g.
If the content of the file “MEMO.TXT” is as follows:
How are you?
Don’t go there
How will you go?
The function COUNT_HOW will display the following message:
Count of how in file 2
Note In the above example, how occurring as a part of word whose is not considered.
(c) Given a binary file “CUSTOMER.DAT, containing records of the following structure type

class Customer
{
char C_Name[20];
char C_Address[30]:
char Area[25];
char C_Phone_No[15];
public:
void Account();
void Disp();
int CheckCode(char AC [])
{
return strcmp(Area, AC);
}
};

Write a function COPYFILE() in C++, that would copy only those records having Area as “SOUTH” from “CUSTOMER.DAT’ to “BACKUR.DAT.

SECTION B

Question 5.
(a) Observe the following EMPLOYEE and MANAGER tables carefully and write the name of the RDBMS operation which will be used to produce the output as shown in RESULT. Also, find the Degree and Cardinality of the RESULT.

(b) Write SQL queries for (i) to (iv) and find outputs for SQL queries (v) to (viii), which are based on the tables.

(i) To display the name of all sports with their SCode.
(ii) To display details of those sports which are having PrizeMoney more than 9000.
(iii) To display the content of the SPORTS table in ascending order of ScheduleDate.
(iv) To display the sum of PrizeMoney for each of the Number of participation groupings (as shown in the column, Number 2 or 4).

(v) SELECT COUNT(DISTINCT Number) FROM SPORTS;
(vi) SELECT MAX(ScheduleDate). MIN(ScheduleDate) FROM SPORTS;
(vii) SELECT A.SportName, A.PrizeMoney,
B.Name FROM SPORTS A, COACH B
WHERE A.SCode=B.SCode AND Name= 'Ravi';
(viii) SELECT SportName, Number, CCode, Name
FROM SPORTS, COACH
WHERE SPORTS.SCode=COACH SCODE AND PrizeMoney>20000;

Question 6.
(a) Using Boolean laws, prove that \(\bar { X } \bar { Y } +\bar { X } +XY=\bar { X } +Y\)
(b) Draw the digital circuit for the function.
\(F\left( X+Y \right) \cdot \left( \bar { X } +\bar { Z } \right) \cdot \left( Y+Z \right)\)
(c) Write the POS form of Boolean function F, which is represented in a truth table as follows:

(d) Reduce the following Boolean expression using K-map:
F(P, Q, R, S) = Π (0, 2, 3, 5, 6, 7, 8, 10, 11, 12, 15)

Question 7.
(a) What are the design goals of XML?
(b) How the firewall protects our network?
(c) How trojan horses are different from worms? Mention any one difference.
(d) Which network device is used to filter data traffic at a network boundary?
(e) DISTANCE EDUCATION is located in DELHI and is planning to go in for networking of 4 wings for better interaction. The details are given below:

(i) Suggest the most appropriate building to building cable layout to connect all three buildings for efficient communication.
(ii) Suggest the most suitable place (i.e. Wing) to house the server with a suitable reason.
(iii) Suggest the type of networking (LAN, MAN, WAN) for connecting Lib Wing to Admin Wing. Justify your answer.
(iv) The institute is planning to link its study center situated in Delhi. Suggest an economical way to connect it with reasonable high speed. Justify your answer.
(f) Categorize the following under Open Source based Software and Proprietary Software.
(i) Adobe Flash Player
(ii) Apache
(iii) Skype
(iv) MySQL
How is an E-mail different from a chat?

Answers

Answer 1.
(a) Identifiers which can be used for naming variable, constant or function in a C++ program are Num2, THIS, Float, _Sum
(b) The following two header files are required to execute the given code:

(i) → strlen()
(ii) → puts()

(c) void main()
{
float x, y, z;
cout<<"Enter two numbers": cin>>x>>y:
cout<<"The numbers in reverse order are"<<y<<x:
}

(d) Output
MaLiQ550
430
(e) Output
50
41 # 92
13 # 240
350 # 0
(f) (iv) 19 : 16: 15: 16: is the correct option.
When I = 2
The minimum value of variable Number can be 15
The maximum value of variable Number can be 18

Answer 2.
(a) Polymorphism is the way of representing one form-multiple behaviour iq a programming language. Function overloading is one example of polymorphism, where more than one function carrying same name behave differently with different set of parameters passed to them.
e.g. Representing function overloading as polymorphism:

void Show()
{
cout<<"Example"<<endl;
}
void Show(int a)
{
cout<<"Value of a "<<a;
}
void main()
{
Show();
Show(5);
}

(b) (i) Function 1 and Function4 combined together referred as constructor overloading, i.e. polymorphism.
(ii) 2 times the message “Course Cancelled” will be displayed. Line3 is responsible to display the message “Course Cancelled”.

(c) class Batsman
{
private:
char bcode[4];
char bname[20];
int innings, notout, runs;
float batavg;
void calcavg();
public:
void readdata();
void displaydata();
};
void Batsman::calcavg()
{
batavg = runs/(innings-notout);
}
void Batsman::readdata()
{
cout<<"Enter the four digit code";
for(int i = 0; i < 4; i++) cin>>bcode[i];
cout<<"Enter name":
gets(bname);
cout<<"Enter innings": cin>>innings ;
cout<<"Enter notout": cin>>notout;
cout<<"Enter runs"; cin>>runs; calcavg():
}
void Batsman::displaydata()
{
cout<<"\nBatsman code:";
fort(int i=0; i<4; i++) .
cout<<bcode[i];
cout<<”\nBatsman Name:”;
puts(bname);
cout<C'\nInnings : "<<innings;
cout<<"\nNotouts:"<<notout;
cout<<"\nRuns:"<<runs;
cout<<"\nThe Average:"<<batavg;
}

(d) (i) Base class of SideShape : Shape
Derived class of SideShape : SubShape
(ii) SideLength, SideWidth, width, height.
(iii) display()
(iv) Multi Level Inheritance

Answer 3.

(a) void Change(int a[], int size)
{
for(int i=0; i<size; i++)
{
if(a[i]%2==0)
a[i]+=6;
else,
a[i]+=8;
}
}

(b) Base address B = 1000
W = 4 bytes
N = 20,
M = 10
L₁= 0,
L₂ = 0
I = 5,
J = 15
X[I][J] = B + W * [{I-L₁) + M*(J – L₂)]
X[5][15] = 1000 + 4 * [(5 – 0) + 10 * (15 – 0)]
= 1000 + 4 *(5 + 150)
= 1000 + 4 * 155 = 1000 + 620
= 1620

(c) void convertdnt a[],int n) //a[] is the 1-D array
{
int an[10][10], i, j, k = 0, 1; //a[][] is the resultant 2-D array.
for(i =0; i < n ; i++)
{
k = n - i;
l = 0;
for(j=0; j<n; j++)
{
if (l! = k)
{
an[i][j] = a[l];
l++;
}
else if (l = k && j ! = n)
an[i ][j] = 0;
}
}
for(i = 0; i < n; i ++)
{
cout<<"\n";
for(j = 0; j < n; j++)
cout<<an[i][j]<<"\t";
}
}

(d) True, False, AND, True, True, NOT, OR, AND


Result: False

(e) struct node
{
int EmpCode;
char EName[15];
node * link;
};
void PUSH(node *T0P, int code, char nm[])
{
node *temp;
temp=new node;
temp->EmpCode=code;
strcpy(temp->EName,nm);
temp->link=NULL;
if (TOP == NULL)
TOP=temp;
else
{
temp->link=TOP;
TOP=temp;
}
}

Answer 4.
(a) 8

(b) void COUNT_HOW()
{
fstream File;
File.open("MEMO.TXT", ios::in);
char word[80]:
int c = 0;
File>>word:
while(!File.eof())
{
for(int i=0; i<strlen(word); i++) word[i] = tolower(word[i]); if(strcmp(word, "how")==0) C++; File>>word;
}
cout<<"Count of how in file "<<c<9000;
(iii) SELECT * FROM SPORTS ORDER BY ScheduleDate;
(iv) SELECT SUM(Prize Money), Number FROM SPORTS GROUP BY Number;

Answer 6.

Answer 7.
(a) The design goals of XML emphasize simplicity, generality, and usability over the Internet.
(b) A firewall is a part of a computer system or network that is designed to block unauthorized access while permitting authorized communications. It is a device or set of devices configured to permit, deny, encrypt, decrypt or proxy all computer traffic between different security domains based upon a set of rules and other criteria.
(c) Difference between trojan horses and worms is as follows:

(d) Bridge
(e) (i) Cable Layout

(ii) Since the maximum number of computers are in the Student Wing. So, a suitable place to house the server is Student Wing.
(iii) Since the difference between Lib Wing and Admin Wing is small, so the type of networking is small, i.e. LAN.
(iv) Broadband connection as it is quite economical and speedy.
(f) Open Source based Software
(i) Adobe Flash Player
(iii) Skype
Proprietary Software
(ii) Apache
(iv) MySQL
(g) The e-mail refers to sending and receiving messages electronically in which the sender and the recipient need not be online at the same time. Attachments of other documents are possible in E-mail. Whereas in chatting, to send and receive messages, both recipient and sender must be online and available over the Internet simultaneously.

We hope the CBSE Sample Papers for Class 12 Computer Science Paper 3 help you. If you have any query regarding CBSE Sample Papers for Class 12 Computer Science Paper 3, drop a comment below and we will get back to you at the earliest.

CBSE Sample Papers for Class 12 Computer Science Paper 2 are part of CBSE Sample Papers for Class 12 Computer Science. Here we have given CBSE Sample Papers for Class 12 Computer Science Paper 2.

CBSE Sample Papers for Class 12 Computer Science Paper 2

Students who are going to appear for CBSE Class 12 Examinations are advised to practice the CBSE sample papers given here which is designed as per the latest Syllabus and marking scheme, as prescribed by the CBSE, is given here. Paper 2 of Solved CBSE Sample Paper for Class 12 Computer Science is given below with free PDF download Answers.

Time: 3 Hours
Maximum Marks: 70

General Instructions:

• All questions are compulsory within each Section.
• Programming Language in SECTION A : C++.
• Answer the questions after carefully reading the text.

SECTION A

Question 1.
(a) Differentiate between the syntax error and runtime error Give one example of each.
(b) Which C++ header file(s) are essentially required to be included to run/execute the following C++ source code?

void main( )
{
int num;
cout<<"Enter the number:";
cin>>num;
if(abs(num)==num)
cout<<"Positive"<<endl; 
}

(c) Observe the following C++ code carefully and rewrite the same after removing all the syntax error(s) present in the code. Ensure that you underline each correction in the code.
Note:
All the desired header files an. already included, which are required to run the code.
Correction should .not change the logic of the program.

Class Student 
{ 
int admno; 
public: 
int Student( ) { admno = 0; } 
void input( ) 
{ 
cin>>admno;
}
void output( )
{
cout<<admno;
}
}
void Main( )
{
Student S;
input(S);
S.output( );
}

(d) Observe the following C++ code carefully and obtain the output, which will appear on the screen after the execution of it.
Note: All the desired header files are already included, which are required to run the code.

int main( )
{
char String[] = "Pointers and Strings";
cout<<*(&String[2] )<<endl;
cout.write(String+5, 15)<<endl;
cout.write(String, 20)<<endl;
return( );
}

(e) Find the output of the following program:
Note: Assume that all required header files are already being inducted.

class Weather
{
int Location, Temp, Humidity;
public:
Weatherdnt L=1)
{
Location = L;
Temp=15;
Humidity=65;
}
void Sun(int T)
{
Temp+=T;
}
void Rain(int H)
{
Humidity+=H;
}
void Check( )
{
cout<<Location<<":"<<Temp<<"&"<<Humidity<<"%"<<endl;
}
};
void main( )
{
Weather W, N(3);
W.Sun(5);
W.Check( );
N.Rain(10);
N.Sun(2);
N.Check( );
W.Rain(15);
W.Check( );
}

(f) In the following C++ program, what is the expected value of MyMarks from options (i) to (iv) given below? Justify your answer.

#include<stdio.h>
#include<iostream.h>
void main( )
{
randomize( );
int Marks[ ] = {99, 92, 94, 96, 93, 95}, MyMarks;
MyMarks = Marks[1+random(2)];
cout<<MyMarks<<endl;
}

(i) 99
(ii) 94
(iii) 96
(iv) 92

Question 2.
(a) What is a copy constructor? Illustrate with the help of C++ code.
(b) Answer the questions (i) and (ii) after going through the following class:

class Meeting
{
int Time;
public:
Meeting( ) //Function1
{
Time = 30;
cout<<"Meeting starts now"<<endl;
}
void Discussion(int) //Function2
{
cout<<”Discussion in the Meeting on"<<endl;
}
Meetingtint Duration) //Function3
{
Time = Duration;
cout<<"Meeting starts now"<<endl;
}
~Meeting( ) //Function4
{
cout<<"Vote for thanks"<>Percentage;
}
void DisplayData( )
{
cout<<setw(12)<<S_Admno;
cout<<setw(32)<<S_Name;
cout<<setw(3)<<Percentage<<endl;
}
int ReturnPercentage( )
{
return Percentage;
}
};

SECTION B

Question 5.
(a) Observe the following table and write the names of the most appropriate columns, which can be considered as (i) Degree and cardinality (ii) Primary key.

(b) Write SQL queries for (i) to (iv) and find outputs for SQL queries (v) to (viii), which are based on the tables.

(i) To display the name of all senders from Mumbai.
(ii) To display recipient details in ascending order of RecName.
(iii) To display Number of Recipients from each city.
(iv) To insert a new row in the table SENDER with the following data ‘KL05′, A.Tiwari’,’12-C Model Town’, ‘Kolkata’.

(v) SELECT DISTINCT SenderCity FROM SENDER;
(vi) SELECT A.SenderName, B.RecName FROM SENDER A, RECIPIENT B
WHERE A.SenderID = B.SenderlD AND B.RecCity = 'Mumbai';
(vii) SELECT RecName. RecAddress FROM RECIPIENT
WHERE RecCity NOT IN (’Mumbai’. ’Kolkata’);
(viii) SELECT RecID, RecName, SenderCity FROM RECIPIENT, SENDER
WHERE RECIPIENT.SenderID=SENDER.SenderID AND SenderCity='New Delhi';

Question 6.
(a) State and verify absorption law rising truth table.
(b) Draw the logic diagram of the expression \(\bar { X } \left( Y+Z \right) +\bar { X } \bar { Y }\)
(c) Write the Product of Sum (POS) form of the function H (U,V,W), truth table representation of H is as follows:

(d) Obtain a simplified form for a Boolean expression using K-map.
F(w, x, y, z) = Σ (0, 1, 3, 5, 7, 9, 10, 11, 12, 13, 15)

Question 7.
(a) What is the use of PPP (Point to Point Protocol)?
(b) What are two types of modem?
(c) Differentiate between freeware and shareware.
(d) What is the importance of URL in networking?
(e) Akash Industry has set-up its new centre at Akansha Kunj and Web-based activities. The company compound has 4 buildings as shown in the diagram below:

(i) Suggest a cable layout of connection between the buildings.
(ii) Suggest the most suitable place (i.e. Building) to house the server of this organisation with a suitable reason.
(iii) Suggest the placement of the following devices with justification
I. Internet Connecting Device/Modem
II. Switch
(iv) The organisation is planning to link its Buy Counter situated in various parts of the same city, which type of network out of LAN, MAN or WAN will be formed? Justify your answer.
(f) Categorises the following under GSM and CDMA:
(i) Switching System (SS)
(ii) Time Division Multiple Access (TDMA)
(iii) Frequency Division Multiple Access (FDMA)
(iv) Operation and Support System (OSS).
(g) What is the significance of term bandwidth? Give unit of bandwidth.

Answers

Answer 1.
(a) Differences between syntax error and runtime error are as follows:

(b) → cout( )
→ abs( )
(c) class Student
{
int admno;
public:
Student() { admno = 0; }
void input( )
{
cin>>admno;
}
void output( )
{
cout<<admno;
}
};
void main( )
{
Student S;
S.input( );
S.output( );
}

(d) The output of the given program would be as given below:
i
ers and Strings
Pointers and Strings
(e) Output
1:20&65%
3:17&75%
1:20&80%
(f) The expected output will be:
(ii) 94
(iv) 92
Because random(2) will generate either 0 or 1. If it will generate 0 then the output will be (iv) 92. If it will generate 1 then the output will be (ii) 94.

Answer 2.
(a) A copy constructor is a special constructor function that copies the contents of an object to another object, i.e. constructs an object using the data of another object of the same class.
e.g. To illustrate the copy constructor

#include<stdio.h>
#include<iostream.h>
class Counter
{
int num;
public:
Counter( ) { num=10; }
Counter(Counter &c) //Copy Constructor
{ num=c.num; }
void Print( )
{
cout<<num<<endl; 
}
};
void main( )
{
Counter obj1;
cout<<"Object 1 variable value
obj1.Print( );
Counter obj2(obj1): //Calling copy constructor
cout<<"Object 2 variable value
obj2.Print( );
}

(b) (i) Concept illustrated by Function 1 and Function3 combinedly is called constructor overloading.
(ii) 1 time the message “Vote for thanks” will be displayed. Line4 is responsible to display the message “Vote for thanks”.

(c) class Dress
{
char CodeC20];
char Type[20];
int Size;
char Material[20];
float Price;
void Cal_Price( )
{
if(strcmp(Material,"Fabric")==0)
{
if (strcmpf Type, "Western" )==0)
Price=2500;
else if(strcmp(Type, "lndian")=0)
Price=2200;
}
else
{
if (strcmpdype, "Western" )==0)
Price=2500-0.20*2500;
else if (strcmp(type,"Indian")==0)
Price=2200-0.20*2200;
}
}
public:
Dress( )
{
strcpy(Code, "NOT ASSIGNED");
strcpy(type, "NOT ASSIGNED");
strcpy(Material,"NOT ASSIGNED");
Size=0;
Price=0;
}
void Input( )
{
cout<<"Enter dress code:"; cin>>Code;
cout<<"Enter type-(Western/Indian):"; cin>>Type;
cout<<"Enter size:"; cin>>Size;
cout<<"Enter material:"; cin>>Material;
Cal_Price( ):
}
void Dispiay( )
{
cout<<"Code:"<<Code<<endl;
cout<<"Type:"<<Type<<endl;
cout<<"Size:"<<Size<<endl;
cout<<"Material:"<<Material<<endl;
cout<<”Price:"<<Price<<endl;
}
};

(d) (i) The member functions inherited by class C are: getVal( ), dispval( ), getData( ), showData( ).
(ii) There is no base class of class B and subclass of class B is class C.
(iii) II. Multiple Inheritance
(iv) Data member, x, with private access scope is directly accessible only inside the class. Data member, z, with protected access scope is directly accessible within the class and by all the child classes of class B. Both the member function, with the public scope are accessible outside the class.

Answer 3.

(a) void Reversearray(int A[ ], int n)
{
int tmp, i, j:
for(i=0, j=n-1; i<=j; i++, j--)
{
tmp = AC[i];
A[i] = A[j]:
A[j] = tmp:
}
for(i=0; i<n; i++)
cout<<A[i ]<<" ";
}

(b) Given,
Element size, W=4 bytes
Total rows, M=20
Total columns, N = 30
I_r = 0
I_c= 0
Address of A[2][20] = 5000
Base address 6 = ?
Column major
A[I][J] = B+W*[(I-I_r) + M*(J-I_c)]
A[2] [20] = B + 4*[(2 – 0) + 20*(20 – 0)]
5000 = B + 4*[2 + 400]
5000 = B + 4*[402]
5000 = 6+1608
B = 5000-1608 = 3392
A[I][J] = B+W*[(I-I_r) + M*(J-I_c)]
A[5][15] =3392 + 4*[(5 – 0) + 20*(15 -0)]
= 3392 + 4*[5 + 300]
= 3392 + 4*[305]
= 3392 + 1220
= 4612

(c) void Remove(MYNODE *Front, MYNODE *Rear)
{
MYNODE *Ptr = Front;
if(Ptr = NULL)
{
cout<<"Underflow!"; 
exit(1); 
} 
else if(Front == Rear) 
{ 
delete Ptr; 
Front = Rear = NULL; 
else 
{ 
Front = Front->Link;
delete Ptr;
}
}

(d) Given expression, (X-Y/(Z + U) *V)

Output XYZU + IV

(e) void SKIP(int A[ ][3], int M, int N)
{
int i, j;
for(i=0; i<=N-1; i++)
{
if(i%2==0)
{
j=0:
}
el se
{
j=1:
}
whi1e(j<=M-1)
{
cout<<A[i][j]<<"\t";
j=j+2;
}
}
}

Answer 4.

(a) (i) Fi.seekp(-1*sizeof (f), ios::cur);
(ii) Fi .write((char*)&M, sizeof(M));

(b) #include<iostream.h>
#1nclude<fstream.h>
#include<ctype.h>
#include<string.h>
void main( )
{
int i = 0, Start = 0;
ifstream fin("Report.txt");
ofstream fout("Finerep.txt");
char word[25];
while(!fin.eof())
{
fin>>word;
if(Start==0)
{
word[0] = toupper(word[0]);
Start=1;
}
for(i=0; i<strlen(word); i++)
if (word[i ]= '.')
word[i+1] = toupper(word[i+1]);
fout<<word;
}
}
(c) void ReadContents( )
{
ifstream ifs;
ifs.open("STUDENT.DAT",ios::in | ios::binary);
if (!ifs)
{
cout<<"file does not exist"; 
exit(0); 
} 
Student St; 
whi1e(ifs.read((char*)&St,sizeof (St))) 
{ 
if(St.ReturnPercentage( )>75)
St.DispiayData( );
}
ifs.close( );
}

Answer 5.
(a) (i) Degree=7
Cardinality = 6
(ii) Primary Key = CoachID

(b) (i) SELECT SenderName FROM SENDER
WHERE SenderCity = "Mumbai";
(ii) SELECT * FROM RECIPIENT ORDER BY RecName;
(iii) SELECT COUNT(*) AS "Number of Recipients", RecCity
FROM RECIPIENT GROUP BY RecCity;
(iv) INSERT INTO SENDER VALUES('KL05' , 'A.Tiwari', '12-C Model Town', 'Kolkata');

Answer 6.

Answer 7.
(a) A point-to-point protocol is a communication protocol used to establish a direct connection between two nodes. It is the Internet standard for transmission of IP packets over serial lines.
(b) The modem comes in two varieties are as follows:
(i) Internal Modems These modems are fixed within a computer.
(ii) External Modems These modems are connected externally to a computer as other peripherals are connected.
(c) Freeware generally refers to the software, which is available for free of cost while shareware refers to the software, which is made available with a right to redistribute copies.
(d) URL stands for Uniform Resource Locator, each page that is created for Web browsing is assigned a URL that effectively serves as the page’s worldwide name or address. URL’s have three parts: the protocol, the DNS name of the machine on which the page is located and a local name uniquely indicating the specific page.
(e) (i) Cable Layout

(ii) The most suitable place to house the server of this organization would be Sugar Mill Building, as this building contains the maximum number of computers thus, decreasing the cabling cost for most of the computers as well as will help to reduce the network traffic.
(iii) I. Sugar Mill Building because it has the maximum number of computers.
II. A switch will be needed in all the buildings to interconnect the group of cables from the different computers in each building.
(iv) MAN because MAN is the networks that link computer facilities within a city.
(f) GSM
(i) Switching System (SS)
(iv) Operation and Support System (OSS)
CDMA
(ii) Time Division Multiple Access (TDMA)
(iii) Frequency Division Multiple Access (FDMA)
(g) Bandwidth is the capability of a medium to transmit an amount of information over a unit of time. The bandwidth of a medium is generally measured in units of bits per second (bps) or more commonly in kilobits per second (Kbps).

We hope the CBSE Sample Papers for Class 12 Computer Science Paper 2 help you. If you have any query regarding CBSE Sample Papers for Class 12 Computer Science Paper 2, drop a comment below and we will get back to you at the earliest.

CBSE Sample Papers for Class 12 Computer Science Paper 1 are part of CBSE Sample Papers for Class 12 Computer Science. Here we have given CBSE Sample Papers for Class 12 Computer Science Paper 1.

CBSE Sample Papers for Class 12 Computer Science Paper 1

Students who are going to appear for CBSE Class 12 Examinations are advised to practice the CBSE sample papers given here which is designed as per the latest Syllabus and marking scheme, as prescribed by the CBSE, is given here. Paper 1 of Solved CBSE Sample Paper for Class 12 Computer Science is given below with free PDF download Answers.

Time: 3 Hours
Maximum Marks: 70

General Instructions:

• All questions are compulsory within each Section.
• Programming Language in SECTION A : C++.
• Answer the questions after carefully reading the text.

SECTION A

Question 1.
(a) Which of the following are not reserved keywords in C++?

WHILE, default, if, IF, do, INCLUDE, int, FLOAT

(b) Which C++ header file(s) will be essentially required to be included to run/execute the following C++ code?

void main( )
{
int Cno = 102; char CName[ ]= "Aayaan";
cout<<setw(5)<<Cno<<setw(25)<<CName<<endl;
}

(c) Rewrite the following program after removing the syntactical error(s), if any. Underline each correction.

#include
#include[stdio.h]
void main( )
{
struct movie
{
char movie_name[20];
char movie_type;
int ticket_cost = 100;
}
MOVIE;
gets(movie_name);
gets(movie_type);
}

(d) Find the output of the following C+ + program code:
Note: Assume all required header files are already being included.

void Change(int a = 25) .
{
for(int I = 10; I <= a; I+ = 4)
cout<<I<<" ";
cout< }
void Update(int &n)
{
n+ = 20:
Change(n);
}
void main()
{
int C = 15:
Update(C); '
Change( ):
cout<<"Number=''<<C<<endl:
}

(e) Find the output of the following program:

class TEACHER
{
int Tid, TeachCode, TeacherCount;
public:
TEACHER(int Thid=1)
{
Tid=Thid;
TeachCode=0;
TeacherCount=0;
}
void Subject(int S=20)
{
TeachCode++;
TeacherCount+=S;
}
void Status( )
{
cout<<Tid<<":"<<TeachCode<<”:”<<TeacherCount<<endl; 
} 
}; 
void main( ) 
{ 
TEACHER T(5), M: 
T.Subject( ); 
M.Subject(50); 
T.Status( ): 
T.Subject(30); 
M.Status( ); 
T. Status( ); 
}

(f) Observe the following program carefully, if the value of Num entered by the user is 5, choose the correct possible output(s) from the options from (i) to (iv). And also find the minimum and maximum value of Rndnum variable. Note: Assume all required header files are already being included. random(n) function will generate an integer between 0 to n-1.

void main( ) 
{ 
randomize( ); 
int Num, Rndnum; 
cin>>Num;
Rndnum = random(Num)+5;
for(int N=1; N<=Rndnum; N++)
cout<<N<<" ";
}

Output
(i) 1 2 3 4
(ii) 1 2
(iii) 1 2 3 4 5 6 7 8 9
(iv) 1 2 3

Question 2.
(a) Explain the transitive nature of inheritance with an example.
(b) Answer the questions (i) and (ii) after going through the following class:

class Vehicle
{
int VehicleNo, Track;
public:
Vehicle( ); // Function1
Vehicle(int VH); // Function2
Vehicle(Vehicle &V); // Function3
void Allocated; // Function4
void Moved; // Function5
};
void main( )
{
Vehicle V;
:
:
}

(i) Out of the following, which option is correct for calling Function2?
Option 1 – Vehicle H(V);
Option 2 – Vehicle P(10);
(ii) Name the feature of object oriented programming which is illustrated by Function1, Function2 and Function3 combined together.
(c) Define the class Student with the following specifications:
Private members
admno integer
sname 20 characters
eng, math, science float
total float
ctotal ( ) A function to calculate eng + math + science

Public members
Takedata( ) function to accept values for admno, sname, eng, math, science and invoke ctotal( ) to calculate total.
Sbowdata( ) function to display all the data members on the screen.
(d) Answer the questions (i) to (iv) based on the following code:

class MANAGER
{
int Mgr_no;
char Mgr_Name[20];
protected:
char Dept[20];
public:
MANAGER( );
void Mentry( );
void Mdisplay( );
};
class EMPLOYEE
{
int emp_no;
char emp_name[20];
protected:
float salary;
public: .
EMPLOYEE( );
void Eentry( );
void Edisplay( );
};
class COMPANY:private MANAGER, public EMPLOYEE
{
char cmp_no[10];
char estb_date[8]:
public:
char description[20];
COMPANY( );
void Centry( );
void Cdetail( ):
};

(i) Which type of inheritance is shown in the above example?
(ii) Write the names of data members which are accessible from objects belonging to class COMPANY.
(iii) Write the names of all the member functions which are accessible from objects belonging to class COMPANY.
(iv) Write the names of all the data members which are accessible from member functions of class EMPLOYEE.

Question 3.
(a) Write a function in C++ which accepts an integer array and its size as arguments and replaces elements having odd values with thrice its value and elements having even values with twice its value.
e.g. If an array of five elements initially contains the elements as 3, 4, 5, 16, 9
Then, the function should rearrange the content of the array as 9, 8, 15, 32, 27
(b) An array P[50] [60] is stored in the memory along the column with each of the element occupying 2 bytes. Find out the memory location for the elements P[10] [20], if the base address of the array is 6800.
(c) Given the necessary declaration of linked implemented queue containing players information (as defined in the following definition of Node). Also, write a user defined function in C++ to delete one player’s information from the queue.

struct Node
{
int PlayerNo;
char PIayerName[20];
Node * Link;
};
class QUEUE( )
{
Node *front, *rear;
public:
QUEUE( )
{
front=rear=Null;
}
void Insert_Node( );
void Delete_Node( );
~QUEUE( );
};

(d) Change the following infix expression into postfix expression:
((A + B) * C + D/E – F)
(e) Write a function in C++ to find the sum of both left and right diagonal elements from a two dimensional array (matrix).
e.g. If array contains
4 3 5
6 7 4
5 6 7
The output will be
Sum of Diagonal 1 : 18
Sum of Diagonal 2 : 17

Question 4.
(a) Find the output of the following C++ code considering that the binary file STU.DAT exists on the hard disk with a data of 50 students.

class Student
{
int Rno;
char Sname[50];
public:
int count( );
};
void main( )
{
fstream f;
f.open("STU.DAT", ios::binary|ios::in);
Student S;
int a=1;
while(a<2)
{
f.read((char*)&S, sizeof(S));
a++ ;
}
int Position=f.tellg( )/sizeof(S);
cout<<"\n Present Student Record:"<<Position<<endl; 
f.close( ); 
}

(b) Write a function in C++ to print the count of the word “is” as an independent word in a text file “DIALOGUE.TXT”. e.g. If the content of the file DIALOGUE.TXT is This is his book. Is this book good? Then the output of the program should be 2.
(c) Assuming a binary file “JOKES.DAT” is containing objects belonging to a class JOKE (as defined below). Write a user-defined function in C++ to add more objects belonging to class JOKE at the bottom of it.

class JOKE, 
{
int Jokeid; // Joke identification number 
char Type[5]; // Joke type 
char Jokedesc[255]; // Joke description 
public; 
void NewJokeEntry( ) 
{ 
cin>>Jokeid;gets(Type);
gets(Jokedesc);
}
void ShowJoke( )
{
cout<<Jokeid<<": "<<Type<<endl<<Jokedesc<<endl;
}
};

SECTION B

Question 5.
(a) Differentiate between primary key and candidate key of a table with the help of an example.
(b) Write SQL queries for (i) to (iv) and find outputs for SQL queries (v) to (viii). Which are based on the tables?

(i) To display the details of all the clients except those whose city is Delhi.
(ii) To display the ClientName, City from table CLIENT and ProductName and Price from table PRODUCT, with their corresponding matching P_ID.
(iii) To display names of those clients whose city is Delhi and has ‘e’ as third letter in their name.
(iv) To display product names and price in decreasing order of price.

(v) SELECT DISTINCT City FROM CLIENT;
(vi) SELECT ManufacturerName, MAX(Price), MIN(Price), COUNT(*)
FROM PRODUCT GROUP BY ManufacturerName;
(vii) SELECT ClientName, ProductName FROM CLIENT, PRODUCT
WHERE CLIENT.P_ID = PRODUCT.P_ID;
(viii) SELECT ProductName, Price, ClientName, City FROM PRODUCT, CLIENT
WHERE PRODUCT.P_ID=CLIENT.P_ID AND Price<90;

Question 6.
(a) Verify the following using Boolean laws:
\(\bar { X } Y+X\bar { Y } +\bar { X } \bar { Y } =\left( \bar { X } +\bar { Y } \right)\)
(b) Write the equivalent Boolean expression for the following logic circuit:

(c) Given the following truth table, derive a Sum of Product (SOP) form of Boolean expression from it:

(d) If F(A, B, C, D) = π(0, 2, 4, 5, 7, 8, 10, 12, 13, 15), obtain the simplified form using K-map.

Question 7.
(a) Which network device is used to amplify the feeble signals when they are transported over a long distance? Also, write its function.
(b) Give two major reasons to have network security.
(c) How does node failure cause network failure in a ring topology?
(d) What is the purpose of using a Web browser? Name any one commonly used Web browser.
(e) Knowledge Supplement Organisation (KSO) has set-up its new center at Bengaluru for its office and Web-based activities. It has 4 blocks of buildings as shown in the diagram below:

(i) Suggest a cable layout of connections among the blocks.
(ii) Suggest the most suitable place, i.e. Block to house the server of this organization with a suitable reason.

(iii) Which type of network out of the following is formed be a connection the computers of these three blocks?
I. LAN
II. MAN
III. WAN

(iv) Which wireless channel out of the following should be opted by (KSO) to connect to people from all over the world?
I. Infrared
II. Microwave
III. Satellite

(f) Categorize the following client side and server side script category:
(i) PHP
(ii) VB Script
(iii) ASP
(iv) JavaScript

(g) List the characteristics of a computer virus.

Answers

Answer 1.
(a) WHILE, IF, INCLUDE, FLOAT are not reserved keywords in C ++.

(b) <iomanip.> → setw( )
<iostraem.h> → cout( )

(c) #include
#include
void main( )
{
struct movie
{
char movie_name[20];
char movie_type;
int ticket cost;
} MOVIE;
MOVIE.ticket cost=100:
qets(MOVIE, movie name):
cin>>MOVIE, movie type:
}

(d) Output
10 14 18 22 26 30 34
10 14 18 22
Number = 35
(e) Output
5 : 1 : 20
1 : 1 : 50
5 : 2 : 50
(f) The possible output is (iii) 1 2 3 4 5 6 7 8 9
The minimum value of Rndnum = 5
The maximum value of Rndnum = 9

Answer 2.
(a) Inheritance is transitive, i.e. if a class B inherits properties of another class A, then all subclasses of B will automatically inherit the properties of class A. This property is called transitive nature of inheritance,
e.g.

class A .
{ int a;
public:
void setA( )
{
cin>>a;
}
};
class B:public A
{
int b;
public:
void setB( )
{
cin>>b;
}
};
class C:public B
{
int c;
public:
void setC( )
{
cin>>c;
}
};

The above example show the transitive nature of inheritance,
(b) (i) Option 2-Vehicle P(10); is correct
(ii) Constructor overloading

(c) class Student
{
int admno;
char sname[20];
float eng, math, science;
float total;
ctotal( )
{
float sum = eng + math + science;
return sum;
}
public:
void Takedata( )
{
cout<<"Enter admission number\n";cin>>admno;
cout<<"Enter your name\n"; gets(sname);
cout<<"Enter marks in English\n"; cin>>eng;
cout<<"Enter marks in Maths\n";cin>>math;
cout<<"Enter marks in Science\n";cin>>science;
ctotal( );
}
void Showdata( )
cout<<"Admi ssion number\n"<<admno<<endl;
cout<<"Name\n"<<sname<<endl;
cout<<"Marks in Engl ish\n"<<eng<<endl;
cout<<"Marks in Maths\n"<<math< cout<<"Marks in Science\n"<<science<<endl;
cout<<"Total Marks\n"<<total;
}
};

(d) (i) Multiple Inheritance
(ii) description
(iii) Centry( ), Cdetail( ), Eentry( ), Edisplay( )
(iv) emp_no, emp_name, salary

Answer 3.

(a) void replace(int *arr, int Size)
{
int i;
for(i=0; i<Size; i++)
if(arr[i]%2 == 0)
arr[i]=arr[i]*2;
else
arr[i]=arr[i]*3;
for(i=0; i<Size; i++)
cout<<arr[i]<<" ";
}

(b) P[50][60]=Base address = 6800
R = 50
Size of element W=2 bytes
I = 10, J = 20, Ir =0, Ic = 0
P[I][J] = B + W*[(I-Ir) + R*(J-Ic)]
P [10][20] =6800 + 2 * [(10 – 0) + 50 * (20 – 0)]
= 6800 + 2 * [10+1000]
= 6800+ 2 *[1010]
= 6800 + 2020 = 8820

(c) void Delete_Node( )
{
Node *P;
if(front==Null)
cout<<"Underflow":
else if (front==rear)
{
P=front;
cout<<"Deleted Node information is";
cout<PlayerNo;
puts(P->playerName);
front=rear=Null;
delete P;
}
else
{
P=front;
cout<<"Deleted Node information is";
cout<PlayerNo;
puts(p->PlayerName);
front-front->Link;
delete P;
}
}

(d) Given, expression as ((A + B)* C + D/E – F)

Hence, the postfix expression is AB + C * D/E-F

(e) void DiagSum(int AC[ ]C5], int N) //A[ ][ ] is a matrix of size m x n and m = n
{
int SumD1=0, SumD2=0;
for(int I=0; I<N; I++)
{
SumD1 =A[I][I]; SumD2+=A[N-I-1][I];
}
cout<<"Sum of Diagonal 1 : "<<SumD1<<endl;
cout<<"Sum of Diagonal 2 : "<<SumD2<<endl; 
}

Answer 4.
(a) Present Student Record: 1

(b) void COUNT( ) 
{
fstream File; 
Fi1e.open("DIALOGUE.TXT", ios::in);
char word[80]; int c=0; 
File>>word;
while(!File.eof(.))
{
for(int i=0; i<strlen(word); i++) 
word[i] = tolower(word[i]); 
if(strcmp(word,"is")=0) C++; 
File>>word;
}
cout<<"count of is in file"<<c<<endl;
File.close( );
}

(c) void AddJoke( )
{
char ans = "y";
fstream file;
file.open("JOKES.DAT", ios::app | ios::binary);
cout<<"want to add an object(y/n)";
ans = getchar( );
while(ans == ’y’)
{
JOKE J1;
J1.NewJokeEntry( );
file.write((char *)&J1, sizeof(J1));
cout<<"want to add an object(y/n)’;
ans = getchar( );
}
file.close( );
}

Answer 5.
(a) A candidate key can be any column or a combination of columns that can qualify as unique key in the database. There can be multiple candidate keys in one table. While the Primary key is a column that uniquely identifies a record. A relation can have only one primary key.

In the EMPLOYEE table, Encode and Regno both can identify uniquely. So, both are candidate keys. Here, we have created Encode as a primary key.

(b) (i) SELECT * FROM CLIENT WHERE City NOT IN (’Del hi');
(ii) SELECT ClientName, City, ProductName, Price FROM CLIENT, PRODUCT
WHERE CLIENT.P_ID = PRODUCT.P_ID;
(iii) SELECT ClientName FROM CLIENT
WHERE City='Delhi' AND ClientName LIKE"__e%";
(iv) SELECT ProductName, Price FROM PRODUCT ORDER BY Price DESC;

Answer 6.

Answer 7.
(a) Repeater: The basic function of a repeater is to amplify the incoming signal and retransmit it, to the other device.
(b) Two major reasons to have network security are as follows:
(i) Security keeps information secure from unauthorized users.
(ii) Authentication determining that the user. is. authorized before sharing sensitive information with or entering into a business deal.
(c) The transmission of data in a ring goes through every connected node on the ring before returning to the sender. If one node fails to pass data through itself, the entire network has failed and no traffic can flow until the defective node has been removed from the rang.
(d) The Web browser fetches the page requested, interprets” the text and formatting commands that it contains and displays the page properly formatted on the screen, e.g. Mozilla Firefox.
(e) (i) Cable Layout

(ii) The most suitable place/block to house the server of this organization would be Block C, as this block contains the maximum number of computers, thus decreasing the cabling cost for most of the computers as well as increasing the efficiency of the maximum computers in the network.
(iii) I. LAN because its coverage area is up to 5 km.
(iv) III. Satellite because its coverage area is in all over the world.
(f) Client-side script
(iii) VB Script
(iv) JavaScript
Server-side script
(i) PHP
(ii) ASP
(g) The following are the characteristics of a computer virus:
(i) it is able to replicate.
(ii) It requires a host program as a carrier.
(iii) It is activated by external action.
(iv) Its replication ability is limited to the system.

We hope the CBSE Sample Papers for Class 12 Computer Science Paper 1 help you. If you have any query regarding CBSE Sample Papers for Class 12 Computer Science Paper 1, drop a comment below and we will get back to you at the earliest.

CBSE Sample Papers for Class 12 Maths Paper 7 are part of CBSE Sample Papers for Class 12 Maths. Here we have given CBSE Sample Papers for Class 12 Maths Paper 7.

CBSE Sample Papers for Class 12 Maths Paper 7

Students who are going to appear for CBSE Class 12 Examinations are advised to practice the CBSE sample papers given here which is designed as per the latest Syllabus and marking scheme as prescribed by the CBSE is given here. Paper 7 of Solved CBSE Sample Paper for Class 12 Maths is given below with free PDF download solutions.

Time: 3 Hours
Maximum Marks: 100

General Instructions:

• All questions are compulsory.
• Questions 1-4 in section A are very short answer type questions carrying 1 mark each.
• Questions 5-12 in section B are short answer type questions carrying 2 marks each.
• Questions 13-23 in section C are long answer I type questions carrying 4 marks each.
• Questions 24-29 in section D are long answer II type questions carrying 6 marks each.

SECTION A

Question 1.
If A is a square matrix of order 3 and |adj A| = 144, then find the value of |3A| ?

Question 2.

Question 3.
Evaluate \(\int { \frac { { sec }^{ 2 }\left( logx \right) }{ x } } dx\)

Question 4.
Differentiate log (x + \(\sqrt { { x }^{ 2 }+{ a }^{ 2 } }\)) with respect to x.

SECTION B

Question 5.
Using elementary transformation find the inverse of the matrix \(\begin{pmatrix} 5 & 4 \\ 3 & 2 \end{pmatrix}\)

Question 6.
Using differentials find the approximate value of f(5.001) where f(x) = x³ – 7x² + 15.

Question 7.
Find the equations of tangents to the curve 3x² – y² = 8 which passes through the point (\(\frac { 4 }{ 3 }\) , 0)

Question 8.
If cos y = x cos (a + y) prove that \(\frac { dy }{ dx } =\frac { { cos }^{ 2 }\left( a+y \right) }{ sina }\)

Question 9.
Find the coordinate of the point where the line \(\frac { x+1 }{ 2 } =\frac { y+2 }{ 3 } =\frac { z+3 }{ 4 }\) meets the plane x + y + 4z = 6.

Question 10.
Let A and B are two events such that P (\(\bar { A\cup B }\)) = \(\frac { 1 }{ 6 }\), P(A ∩ B) = \(\frac { 1 }{ 4 }\) and P(\(\bar { A }\)) = \(\frac { 1 }{ 4 }\) .Prove that A and B are independent events.

Question 11.
Solve for x, tan^-12x + tan^-13x = \(\frac { \pi }{ 4 }\)

Question 12.
Evaluate \(\int { \frac { x-4 }{ \left( x-2 \right) ^{ 3 } } } { e }^{ x }dx\)

SECTION C

Question 13.

Question 14.

Question 15.

Question 16.

Question 17.

Question 18.
Form the differential equation of the family of circles in the first quadrant which touches the coordinate axes.

Question 19.

Question 20.

Question 21.
An instructor has a question bank consisting of 300 easy True/False questions, 200 difficult True/False questions, 500 easy multiple choice questions and 400 difficult multiple choice questions. If a question is selected at random from the question bank, what is the probability that it will be an easy question given that it is a multiple choice question.

Question 22.
An insurance company insured 2000 scooters and 3000 motorcycles. The probability of an accident involving a scooter is 0.01 and that of a motorcycle is 0.02. An insured vehicle met with an accident. Find the probability that the accidented vehicle was a motorcycle. How we can avoid accidents?

Question 23.

SECTION D

Question 24.
If the sum of the lengths of the hypotenuse and a side of a right angled triangle is given, show that the area of the triangle is maximum when the angle between them is \(\frac { \pi }{ 3 }\).
OR
A tank with rectangular base and rectangular sides, open at the top is to be constructed so that its depth is 2 m and volume is 8m³. If building of tank cost ₹ 70 per square metre for the base and ₹ 45 per square metre for the sides, what is the cost of least expensive tank?

Question 25.
Find the area of the region included between the parabola y² = x and the line x + y = 2 using integration.
OR
Find the area of the smaller region bounded by the ellipse \(\frac { { x }^{ 2 } }{ 9 } +\frac { { y }^{ 2 } }{ 4 } =1\) and the line \(\frac { x }{ 3 } +\frac { y }{ 2 } =1\) using integration.

Question 26.
If \(A=\left( \begin{matrix} 3 & 2 & -1 \\ -2 & 1 & 2 \\ 1 & -3 & 1 \end{matrix} \right)\) , find A^-1. Hence solve the system of linear equations
3x – 2y + z = 2
2x + y – 3z = – 5
-x + 2y + z = 6

Question 27.
A company manufactures two types of toys. Toys of Type A require 5 minutes each for cutting and 10 minutes each for assembling. Toys of type B require 8 minutes each for cutting and 8 minutes each for assembling. There are 3 hours 20 minutes available for cutting and 4 hours available for assembling. The profit is ₹ 0.50 each for type A and ₹ 0.60 each for type B toys. How many toys of each type should be manufactured in order to maximize the profit?

Question 28.
The points A (4, 5, 10), B(2, 3, 4) and C(1, 2, -1) are three vertices of a parallelogram ABCD. Find the vector and cartesian equation of the sides AB and BC and find coordinates of D.
OR
Find the angle between lines whose direction cosines are given by the relations 3l + m + 5n = 0 and 6mn – 2nl + 5lm = 0

Question 29.
Solve the differential equation \(\frac { dy }{ dx }\) = sin (x + y) + cos (x + y)

Solutions

Solution 1.

Solution 2.

Solution 3.

Solution 4.

Solution 5.

Solution 6.

Solution 7.

Solution 8.

Solution 9.

Solution 10.

Solution 11.

Solution 12.

Solution 13.

Solution 14.

Solution 15.

Solution 16.

Solution 17.

Solution 18.
Equation of family of circle in the first quadrant which touches both the coordinate axes is

Solution 19.

Solution 20.

Solution 21.
Let E₁ is the event: it is an easy question
E₂ is the event: it is an M.C.Q (Multiple Choice Question)
True/False Easy Question = 300
True/False Difficult Question = 200
MCQ easy question = 500
Difficult MCQ = 400
Total Questions = 300 + 200 + 500 + 400 = 1400
Total easy questions = 300 + 500 = 800
Total difficult questions = 200 + 400 = 600
E₁ ∩ E₂ = easy M.C.Q = 500
E₂ = 500 + 400 = 900

Solution 22.
E₁ : Total insured scooters = 2000
E₂ : Total insured motorcycles = 3000
Total vehicles = 5000
A is the event insured vehicle meets with an accident.

Solution 23.

Solution 24.

Solution 25.

Solution 26.

Solution 27.
Let x type A and y type B toys manufactured.

Hence profit is maximum at the point (8, 20) means 8 toys of type A and 20 toys of type B should be manufactured.

Solution 28.
In parallelogram diagonal bisect to each other, so mid point of BD = Mid point of AC

Solution 29.

We hope the CBSE Sample Papers for Class 12 Maths Paper 7 help you. If you have any query regarding CBSE Sample Papers for Class 12 Maths Paper 7, drop a comment below and we will get back to you at the earliest.