Computer Science Class XII (2016-17)

SQP – Computer Science (Code: 083) Class XII (2016-17) Time: 3Hrs. MM: 70 Instructions: i. All Questions are Compulsory. ii. Programming Language : Section – A : C++ iii. Programming Language : Section – B : Python iv. Answer either Section A or B and Section C is compulsory

Section – A

1 (a) Explain Conditional Operator with suitable example? 2 Conditional operator is also known as ternary operator because it requires three operands and can be used to replace simple if-else code. It is used to check the condition and execute first expression if condition is true else execute other. 

Syntax:

Conditional expression? Expression 1 : Expression 2;

Explanation: If the conditional expression is true then expression 1 executes otherwise expression 2 executes. 

Example:

CPP

int y = 10, x;
x = y > 10 ? 1 : 0;
cout << x;

Output:

0

(b) Which C++ header file(s) are essentially required to be included to run/execute the following C++ code : 1

CPP

void main()
{
    char *word1 = "Hello", *word2 = "Friends";
    strcat(word1, word2);
    cout << word1;
}

<iostream.h> for input output <string.h> for strcat function (c) Rewrite the following program after removing the syntactical errors (if any). Underline each correction.

CPP

#include <conio.h>
#include <iostream.h>
#include <stdio.h>
#include <string.h>
class product {
    int product_code, qty, price;
    char name[20];

public:
    product()
    {
        product_code = 0;
        qty = 0;
        price = 0;
        name = NULL;
    }
    void entry()
    {
        cout << "\n Enter code, qty, price";
        cin >> product_code >> qty >> price;
        gets(name);
    }
    void tot_price() { return qty * price; }
};
void main()
{
    p product;
    p.entry();
    cout << tot_price();
}

Correction in the code:

CPP

#include <conio.h>
#include <iostream.h>
#include <stdio.h>
#include <string.h>
class product {
    int product_code, qty, price;
    char name[20];

public:
    product()
    {
        product_code = 0;
        qty = 0;
        price = 0;
        strcpy(name, NULL);
    }
    void entry()
    {
        cout << "\n Enter code, qty, price";
        cin >> product_code >> qty >> price;
        gets(name);
    }
    int tot_price() { return qty * price; }
};
void main()
{
    product p;
    p.entry();
    cout << p.tot_price();
}

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

CPP

void change(int* s)
{
    for (int i = 0; i < 4; i++) {
        if (*s < 40) {
            if (*s % 2 == 0)
                *s = *s + 10;
            else
                *s = *s + 11;
        }
        else {
            if (*s % 2 == 0)
                *s = *s - 10;
            else
                *s = *s - 11;
        }
        cout << *s << " ";
        s++;
    }
}
void main()
{
    int score[] = { 25, 60, 35, 53 };
    change(score);
}

Ans:

36 50 46 42

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

CPP

class seminar {
    char topic[30];
    int charges;

public:
    seminar()
    {
        strcpy(topic, "Registration");
        charges = 5000;
    }
    seminar(char t[])
    {
        strcpy(topic, t);
        charges = 5000;
    }
    seminar(int c)
    {
        strcpy(topic, "Registration with Discount");
        charges = 5000 - c;
    }
    void regis(char t[], int c)
    {
        strcpy(topic, t);
        charges = charges + c;
    }
    void regis(int c = 2000)
    {
        charges = charges + c;
    }
    void subject(char t[], int c)
    {
        strcpy(topic, t);
        charges = charges + c;
    }
    void show()
    {
        cout << topic << "@" << charges << endl;
    }
};
void main()
{
    seminar s1, s2(1000), s3("Genetic Mutation"), s4;
    s1.show();
    s2.show();
    s1.subject("ICT", 2000);
    s1.show();
    s2.regis("Cyber Crime", 2500);
    s2.show();
    s3.regis();
    s3.show();
    s4 = s2;
    s4.show();
    getch();
}

Output:

Registration@5000
Registration with Discount@4000
ICT@7000
Cyber Crime@6500
Genetic Mutation@7000
Cyber Crime@6500

(f) Observe the following program carefully and attempt the given questions:

CPP

#include <conio.h>
#include <iostream.h>
#include <stdlib.h>
void main()
{
    clrscr();
    randomize();
    char courses[][10] = { "M.Tech", "MCA", "MBA", "B.Tech" };
    int ch;
    for (int i = 1; i <= 3; i++) {
        ch = random(i) + 1;
        cout << courses[ch] << "\t";
    }
    getch();
}

I. Out of all the four courses stored in the variable courses, which course will never be displayed in the output and which course will always be displayed at first in the output? As loop is beginning from 1 and not 0, M.Tech will never be displayed in the output. MCA will always be displayed at first in the output as it is at index 1. II. Mention the minimum and the maximum value assigned to the variable ch? Minimum value of ch=1 Maximum value of ch=3 2(a) What do you understand by Function overloading or Functional polymorphism? Explain with suitable example. It is a method of using the same function or method to work using different sets of input. Function overloading is one of the example of polymorphism, where more than one function carrying same name behave differently with different set of parameters passed to them. 

CPP

void show()
{
    cout <<”\n Hello World !”;
}
void show(char na[])
{
    cout <<”\n Hello World !Its ”<< na;
}

(b) Answer the questions(i) and (ii) after going through the following class:

CPP

class planet {
    char name[20];
    char distance[20];

public:
    planet() // Function 1
    {
        strcpy(name, "Venus");
        strcpy(distance, "38 million km");
    }
    void display(char na[], char d[]) // Function 2
    {
        cout << na << "has " << d << " distance from Earth" << endl;
    }
    planet(char na[], char d[]) // Function 3
    {
        strcpy(name, na);
        strcpy(distance, d);
    }
    ~planet() // Function 4
    {
        cout << "Planetarium time over!!!" << endl;
    }
};

I. What is Function 1 referred as? When will it be executed? I. Constructor. It will be executed at the time of object creation. II. Write suitable C++ statement to invoke Function. 2 II. planet p; p.display(“Pluto”, ”7.5 Billion Km”); (c) Define a class DanceAcademy in C++ with following description: Private Members Enrollno of type int Name of type string Style of type string Fee of type float A member function chkfee( ) to assign the value of fee variable according to the style entered by the user according to the criteria as given below:

Style         Fee
Classical     10000
Western       8000
Freestyle     11000

Public Members A function enrollment() to allow users to enter values for Enrollno, Name, Style and call function chkfee()to assign value of fee variable according to the Style entered by the user. A function display() to allow users to view the details of all the data members. 

CPP

class DanceAcademy {
    int Enrollno;
    char Name[20];
    char Style[20];
    float Fee;
    void chkfee()
    {
        if (strcmpi(Style, "Classical") == 0)
            Fee = 10000;
        else if (strcmpi(Style, "Western") == 0)
            Fee = 8000;
        else if (strcmpi(Style, "Freestyle") == 0)
            Fee = 11000;
    }

public:
    void enrollment()
    {
        cout << "Please enter Enrollno, Name, Style";
        cin >> Enrollno;
        gets(Name);
        gets(Style);
        chkfee();
    }
    void display()
    {
        cout << "\n Entered Enrollno, Name, Style and Fee is:
                "<<Enrollno<<"\t "<<Name<<"\t "<<Style<<"\t "<<Fee;
    }
};

(d) Answer the questions (i) to (iv) based on the following:

CPP

class indoor_sports {
    int i_id;
    char i_name[20];
    char i_coach[20];

protected:
    int i_rank, i_fee;
    void get_ifee();

public:
    indoor_sports();
    void iEntry();
    void ishow();
};
class outdoor_sports {
    int o_id;
    char o_name[20];
    char o_coach[20];

protected:
    int orank, ofee;
    void get_ofee();

public:
    outdoor_sports();
    void oEntry();
    void oshow();
};
class sports : public indoor_sports, protected outdoor_sports {
    char rules[20];

public:
    sports();
    void registration();
    void showdata();
};

(i) Name the type of inheritance illustrated in the above C++ code. Multiple Inheritance. (ii) Write the names of all the members, which are accessible from the objects belonging to class outdoor_sports. Data Members: None Member Functions: oEntry(), oShow() (iii) Write the names of all the member functions, which are accessible from the member function of class sports. registration(), showdata(), oEntry(), oShow(), get_ofee(), iEntry(), iShow(), get_ifee() (iv) What will be the size of the object belonging to class indoor_sports? 46 Bytes 3(a) Write the definition of a function grace_score (int score [], int size) in C++, which should check all the elements of the array and give an increase of 5 to those scores which are less than 40. 3 Example: if an array of seven integers is as follows: 45, 35, 85, 80, 33, 27, 90 After executing the function, the array content should be changed as follows: 45, 40, 85, 80, 38, 32, 90

CPP

void grace_score(int score[], int size)
{
    for (int i = 0; i < size; i++) {
        if (score[i] < 40)
            score[i] = score[i] + 5;
        cout << score[i] << " ";
    }
}

(b) An array P[30][20] is stored along the column in the memory with each element requiring 2 bytes of storage. If the base address of the array P is 26500, find out the location of P[20][10]. 3 Total number of rows= 30 Total size= 2 bytes Base Address= 26500 LOC (P[I][J]) = BaseAddress+((I-LBR) + (J-LBC) * R)*W Assuming Lower Bound of Row(LBR)=0 Lower Bound of Column(LBC)=0 Total number of Rows(R)=30 Size of each element(W)=2 LOC(P[20][10])= 26500 +((20-0)+(10-0)*30)*2 LOC(P[20][10])= 26500 +640 LOC(P[20][10])= 27140 (c) Write the definition of a member function push() for a class Library in C++ to insert a book information in a dynamically allocated stack of books considering the following code is already written as a part of the program:

CPP

struct book {
    int bookid;
    char bookname[20];
    book* next;
};
class Library {
    book* top;

public:
    Library()
    {
        top = NULL;
    }
    void push();
    void pop();
    void disp();
    ~Library();
};

Ans: 

CPP

void Library::push()
{
    book* nptr;
    nptr = new book;
    cout << "Enter values for bookid and bookname";
    cin >> nptr->bookid;
    gets(nptr->bookname);
    nptr->next = NULL;
    if (top == NULL)
        top = nptr;
    else {
        nptr->next = top;
        top = nptr;
    }
}

(d) Write a user-defined function swap_row(int ARR[ ][3], int R, int C) in C++ to swap the first row values with the last row values: For example if the content of the array is: 10 20 30 40 50 60 70 80 90 Then after function call, the content of the array should be: 70 80 90 40 50 60 10 20 30

CPP

void swap_row(int ARR[][3], int R, int C)
{
    for (int i = 0, j = 0; j < C; j++) {
        int temp = ARR[i][j];
        ARR[i][j] = ARR[R - 1][j];
        ARR[R - 1][j] = temp;
    }
}

(e) Evaluate the following POSTFIX expression. Show the status of Stack after execution of each operation separately: 45, 45, +, 32, 20, 10, /, -, *

Element Scanned   Stack Status
45                45
45                45, 45
+                 90
32                90, 32
20                90, 32, 20
10                90, 32, 20, 10
/                 90, 32, 2
-                 90, 30
*                 2700

Hence the final result is 2700 4(a) Find the output of the following C++ code considering that the binary file already exists on the hard disk with 2 records in it.

CPP

class sports {
    int id;
    char sname[20];
    char coach[20];

public:
    void entry();
    void show();
    void writing();
    void reading();
} s;

void sports::reading()
{
    ifstream i;
    i.open("sp.dat");
    while (1) {
        i.read((char*)&s, sizeof(s));
        if (i.eof())
            break;
        else
            cout << "\n"
                 << i.tellg();
    }
    i.close();
}
void main()
{
    s.reading();
}

Ans: 42 84 (b) Write a user defined function word_count() in C++ to count how many words are present in a text file named “opinion.txt”. For example, if the file opinion.txt contains following text: Co-education system is necessary for a balanced society. With co-education system, Girls and Boys may develop a feeling of mutual respect towards each other. The function should display the following: Total number of words present in the text file are: 24

CPP

void word_count()
{
    ifstream i;
    char ch[20];
    int c = 0;
    i.open("opinion.txt ");
    while (!i.eof()) {
        i >> ch;
        c = c + 1;
    }
    cout << " Total number of words present in the text file are: “<<c;
}

(c) Write a function display () in C++ to display all the students who have got a distinction(scored percentage more than or equal to 75) from a binary file “stud.dat”, assuming the binary file is containing the objects of the following class:

CPP

class student {
    int rno;
    char sname[20];
    int percent;

public:
    int retpercent()
    {
        return percent;
    }
    void getdetails()
    {
        cin >> rno;
        gets(sname);
        cin >> percent;
    }
    void showdetails()
    {
        cout << rno;
        puts(sname);
        cout << percent;
    }
};

CPP

void display()
{
    student s;
    ifstream i(“stud.dat”);
    while (i.read((char*)&s, sizeof(s))) {
        if (s.retpercent() >= 75)
            s.showdetails();
    }
    i.close();
}

Section – B (Python)

1 (a) Carefully observe the following python code and answer the questions that follow:

PYTHON3

x = 5
def func2():
    x = 3
    global x
    x = x + 1
    print x
    print x

On execution the above code produces the following output.

6
3

Explain the output with respect to the scope of the variables. 2 Names declared with global keyword have to be referred at the file level. This is because the global statement indicates that the particular variable lives in the global scope. If no global statement is being used, the variable with the local scope is accessed. Hence, in the above code the statement succeeding the statement global x informs python to increment the global variable x Hence the output is 6 i.e 5+1 which is also the value for global x. (b) Name the modules to which the following functions belong: 1 a. uniform() b. fabs() a. random() b. math() (c) Rewrite the following code after removing the syntactical errors (if any). Underline each correction. 2

PYTHON3

def chksum:
     x = input("Enter a number")
     if (x % 2 = 0):
        for i range (2 * x):
           print i
        loop else:
           print "#"

PYTHON3

def chksum():
 x = input("Enter a number")
 if (x % 2 == 0):
   for i in range(2 * x):
     print i
 else:
     print "#"

(d) Observe the following Python code carefully and obtain the output, which will appear on the screen after execution of it. 2 

PYTHON3

def Findoutput():
      L = "earn"
      X = " "
      L1 = []
      count = i
      for i in L:
          if i in ['a', 'e', 'i', 'o', 'u']:
              X = X + i.swapcase()
          else
              if(count % 2 != 0):
                  X = X + str(len(L(:count)))
              else:
                  X = X + i
          count = count + 1
      print X
Findoutput()

Output:

 EA3n

(e) What output will be generated when the following Python code is executed? 3

PYTHON3

def Changelist():
    L = []
    L1 = []
    L2 = []
    for i in range (1, 10):
        L.append(i)
    for i in range (10, 1, -2):
        L1.append(i)
    for i in range (len(L1)):
        L2.append(L1[i]+L[i])
    L2.append(len(L)-len(L1))
    print L2
Changelist()

(f) Observe the following program and answer the questions that follow: 

PYTHON3

import random
X = 3
N = random.randint(1, X)
for i in range(N):
   print i, '#', i + 1

a. What is the minimum and maximum number of times the loop will execute? Minimum Number = 1 Maximum Number = 3 b. Find out, which line of output(s) out of (i) to (iv) will not be expected from the program? i. 0#1 ii. 1#2 iii. 2#3 iv. 3#4 Line iv is not expected to be a part of the output 2a. Explain the two strategies employed by Python for memory allocation. Python uses two strategies for memory allocation: i. Reference counting ii. Automatic garbage collection. Reference Counting: works by counting the number of times an object is referenced by other objects in the system. When an object’s reference count reaches zero, Python collects it automatically. Automatic Garbage Collection: Python schedules garbage collection based upon a threshold of object allocations and object deallocations. When the number of allocations minus the number of deallocations are greater than the threshold number, the garbage collector is run and the unused block of memory is reclaimed. b. Observe the following class definition and answer the questions that follow:

PYTHON3

class Info:
    ips = 0
    def__str__(self):   # Function 1
       return "Welcome to the Info Systems"
    def__init__(self):
       self.__Systemdate = " "
       self.Systemtime = " "
    def getinput(self):
       self.__Systemdate = raw_input("Enter data")
       self.Systemtime = raw_input("Enter data")
       Info.incrips()
    @staticmethod      # Statement 1
    def incrips():
       Info.ips = Info.ips + 1
       print "System invoked", Info.ips, "times"
I = Info()
I.getinput()
print I.systemtime
print __Systemdate    # Statement 2

i. Write statement to invoke Function 1. print I ii. On Executing the above code, Statement 2 is giving an error explain. The statement 2 is giving an error because __Systemdate is a private variable and hence cannot be printed outside the class. c Define a class PRODUCT in Python with the following specifications. Data members: Pid – A string to store product id. Pname – A string to store the name of the product. Pcostprice – A decimal to store the cost price of the product Psellingprice – A decimal to store Selling Price Margin – A decimal to be calculated as Psellingprice – Pcostprice Remarks – To store ”Profit” if Margin is positive else “Loss” if Margin is negative. Member Functions: A constructor function to initialize All the data members with valid default values. A method SetRemarks() that assigns Margin as Psellingprice – Pcostprice and sets Remarks as mentioned below:

Margin               Remarks
<0 (negative)        Loss
>0 (positive)        Profit

A method Getdetails() to accept values for Pid, Pname, Pcostprice, Psellingprice and invokes SetRemarks() method. A method Setdetails() that displays all the data members.

PYTHON3

class PRODUCT:
    def__init__(self):
         self.Pid = "  "
         self.Pname = " "
         self.Pcostprice = 0.0
         self.Psellingprice = 0.0
         self.Margin = 0.0
         self.Remarks = " "

    def SetRemarks(self):
         self.Margin = self.Psellingprice - self.Pcostprice
         if ( self.Margin < 0):
               self.Remarks = "Loss"
         else:
               self.Remarks = "Profit"

    def Getdetails(self):
         self.Pid = raw_input(" Enter Product Id ")
         self.Pname = raw_input(" Enter Product Name ")
         self.Pcostprice = raw_input(" Enter Cost Price ")
         self.Psellingprice = raw_input(" Enter Selling Price ")
         self.SetRemarks()

    def Setdetails(self):
        print "Product Id", self.Pid
        print "Product Name", self.Pname
        print "Cost Price", self.Pcostprice
        print "Selling Price", self.Psellingprice
        print "Margin:", self.Margin
        print "Incurred:", self.Remarks

d. Answer the questions (i) to (iv) based on the following: 4

PYTHON3

class Shop(object):
    def__init__(self):
         self.no__of__employees = 0
         self.no__of__brands = 0
    def getSdata(self):
         self.no__of__employees = input("Number of employees")
         self.no__of__brands = input("Number of brands")
    def showSdata(self):
         print self.no__of__employees
         print self.no__of__brands
class Brand(object):
    def__init__(self):
         self.name = " "
         self.category = ["Men", "Women, "Kids"]
         self.avgprice = 0.0
    def getdata(self):
         self.name = raw_input("Enter Brand Name")
         self.avgprice = input("Enter Average price")
    def showdata (self)
         print self.name
         print self.category
         print self.avgprice
Class Mall(Brandshop):
    def__init__(self):
         self__no__of__shops = 0
    def getdata(self):
         super(Mall, self).getSdata()
         super(Mall, self).getdata()
         self.no__of__shops = input("Enter no of shops")
    def showdata(self):
         print self__no__of__shops
         print self__no__of__shops

i. Which type of Inheritance is demonstrated in the above code? Multiple Inheritance ii. Explain Statement 1 and 2. Statement 1 and 2 invoke the getSdata() function of class Shop and getData() function of class Brand respectively. iii. Name the methods that are overridden along with their class name. getdata() method of class Brand is overridden. When object of class Mall is created, M = Mall() M.getdata() getdata() method of class Mall is invoked and not of class Brand is called. iv. Fill Blank 1 with a statement to display variable category of class Brand. print Brand().category 3a. Consider the following unsorted list: 95 79 19 43 52 3 Write the passes of bubble sort for sorting the list in ascending order till the 3rd iteration. 3 Solution: [79, 19, 43, 52, 3, 95] [19, 43, 52, 3, 79, 95] [19, 43, 3, 52, 79, 95] b. Kritika was asked to accept a list of even numbers but she did not put the relevant condition while accepting the list of numbers. You are required to write a code to convert all the odd numbers into even by multiplying them by 2. 3

PYTHON3

def oddtoeven(L):
    for i in range(len(L)):
        if (L[i] % 2 != 0):
             L[i] = L[i] * 2

c. Aastha wants to create a program that accepts a string and display the characters in the reverse order in the same line using a Stack. She has created the following code, help her by completing the definitions on the basis of requirements given below : 4 class mystack: def __init__(self): self.mystr= ________________ # Accept a string self.mylist =________________ # Convert mystr to a # list Write code to display while removing elements from the stack. def disp(self): : :

PYTHON3

class mystack:
   def __init__(self):
       self.mystr = raw_input("Enter the string")
       self.mylist = list(self.mystr)

  def display(self):
       x = len(self.mylist)
       if(x>0):
             for i in range(x):
                 print self.mylist.pop()
       else:
             print"Stack is empty"

d. Write a generator function generates q() that displays the squareroots of numbers from 100 to n where n is passed as an argument. 2

PYTHON3

import math
def generatesq(n):
    for i in range (100, n):
        yield (math.sqrt(i))

e. Evaluate the following Postfix expression: 20, 10, -, 15, 3, /, +, 5, *

Symbol   Operation       Stack    Result
20       Push            20
10       Push            20, 10
-        Pop(10)         
         Pop(20)
         Push(20-10)
         =10
15      Push             10, 15
3       Push             10, 15, 3
/       Pop(3)
        Pop(15)
        Push(15/3)
        =5               10, 5
+       Pop(5)
        Pop(10)
        Push(10+5)=15    15 
5       Push             15, 5
*       Pop(5)
        Pop(15)
        Push(15*5)
        =75              75         75 

4a Observe the following code and answer the questions that follow: File = open(“Mydata”, “a”) _____________________ #Blank1 File.close() i. What type (Text/Binary) of file is Mydata? Text File ii. Fill the Blank 1 with statement to write “ABC” in the file “Mydata” File.write(“ABC”) b) A text file “Quotes.Txt” has the following data written in it: Living a life you can be proud of Doing your best Spending your time with people and activities that are important to you Standing up for things that are right even when it’s hard Becoming the best version of you Write a user defined function to display the total number of words present in the file.

c. Consider the following class declaration and answer the question that follows:

PYTHON3

import pickle
class student:
    def__int__(self):
        self.name = ""
        self.percent = 0.0
   def inputdata (self):
        self.name = raw_input("Enter name)
        self.percent = input("Enter Percentage scored")
   def returnpercent (self):
        return (self.percent)
   def displaydata(self):
        print "Name:", self name
        print "Percent:", self.percent

Anuj has been asked to display all the students who have scored less than 40 for Remedial Classes. Write a user defined function to display all those students who have scored less than 40 from the binary file “Student.dat” assuming it stores all the object of the class Student mentioned above. 3

PYTHON3

def displaydata():
     X = open ("student.dat", "rb")
     S = Student()
     try:
        while (X):
            S = pickle.load(X)
            if (S.returnpercent()<40);
                S.displaydata()
     except EOFError:
        pass
     X.close()

Section – C 5 (a) Observe the table ‘Club’ given below:

Club
Member_id   Member_Name   Address   Age   Fee
M002        Nisha         Gurgaon     19   3500
M003        Niharika      New Delhi  21   2100
M004        Sachin        Faridabad  18   3500

i. What is the cardinality and degree of the above given table? Cadinality: 4 Degree: 5 ii. If a new column contact_no has been added and three more members have joined the club then how these changes will affect the degree and cardinality of the above given table. Cardinality: 7 Degree: 6 (b) Write SQL commands for the queries (i) to (iv) and output for (v) to(viii) based on the tables ‘Watches’ and ‘Sale’ given below.

Watches
Watchid   Watch_Name   Price   Type   Qty_Store
W001      HighTime      10000  Unisex  100
W002      LifeTime      15000  Ladies  150
W003      Wave          20000  Gents   200
W004      HighFashion   7000   Unisex  250
W005      GoldenTime    25000  Gents   100

Sale
Watchid   Qty_Sold    Quarter
W001       10          1
W003       5           1
W002       20          2
W003       10          2
W001       15          3
W002       20          3
W005       10          3
W003       15          4

i. To display all the details of those watches whose name ends with ‘Time’

select * from watches where watch_name like ‘%Time’ 

ii. To display watch’s name and price of those watches which have price range in between 5000-15000.

select watch_name, price from watches where price between 5000 and 15000;

iii. To display total quantity in store of Unisex type watches.

select sum(qty_store) from watches where type like ’Unisex’;

iv. To display watch name and their quantity sold in first quarter.

 select watch_name, qty_sold from watches w, sale s where
       w.watchid=s.watchid and quarter=1;

v. select max(price), min(qty_store) from watches; Output:

max(price)    min(qty_store)
25000         100 

vi. select quarter, sum(qty_sold) from sale group by quarter;

quarter    sum(qty_sold)
1           15
2           30
3           45
4           15 

vii. select watch_name, price, type from watches w, sale s where w.watchid!=s.watchid; Output:

watch_name    price     type
HighFashion   7000      Unisex 

viii. select watch_name, qty_store, sum(qty_sold), qty_storesum(qty_sold) “Stock” from watches w, sale s where w.watchid=s.watchid group by s.watchid; Output:

watch_name    qty_store    qty_sold   Stock
HighTime      100          25          75
LifeTime      150          40          110
Wave          200          30          170
GoldenTime    100          10          90 

6 (a) Correct the following boolean statements:

1. X+1 = X
2. (A')'=A'
3. A+A'=0
4. (A+B)' = A.B

Correction:

1. X+1 =1 or X+0=X
2. ((A’)’) = A
3. A+A’= 1 or A.A’=0
4. (A+B)’ = A’.B’

(b) Draw the equivalent logic circuit for the following Boolean expression: (A.B)+C 1 (c) Write the POS form of a Boolean Function F, which is represented in a truth table as follows: 2

P   Q   R   F
0   0   0   0
0   0   1   1
0   1   0   1
0   1   1   1
1   0   0   0
1   0   1   1
1   1   0   0
1   1   1   1

Answer: (P+Q+R).(P’+Q+R).(P’+Q’+R) (d) Reduce the following Boolean Expression using K Map: F(A, B, C, D)= (0, 1, 3, 5, 6, 7, 9, 10, 11, 13, 14, 15) 7 (a) Identify the type of topology on the basis of the following: 1. Since every node is directly connected to the server, a large amount of cable is needed which increases the installation cost of the network. 2. It has a single common data path connecting all the nodes. Answer: 1. Star Topology 2. Bus Topology (b) Expand the following: 1 a. VOIP: Voice Over Internet Protocol b. SMTP: Simple Mail Transfer Protocol (c) Who is a hacker? 1 A computer enthusiast, who uses his computer programming skills to intentionally access a computer without authorization is known as hacker. A hacker accesses the computer without the intention of destroying data or maliciously harming the computer. (d) The following is a 32 bit binary number usually represented as 4 decimal values, each representing 8 bits, in the range 0 to 255 (known as octets) separated by decimal points 140.179.220.200. What is it? What is its importance? 1 It is an IP Address.It is used to identify the computers on a network. (e) Daniel has to share the data among various computers of his two offices branches situated in the same city. Name the network (out of LAN, WAN, PAN and MAN) which is being formed in this process. 1 Answer: MAN (f) Rehaana Medicos Center has set up its new center in Dubai. It has four buildings as shown in the diagram given below:

Distances between various buildings are as follows:
Accounts to Research Lab        55 m
Accounts to Store               150 m
Store to Packaging Unit         160 m
Packaging Unit to Research Lab  60 m
Accounts to Packaging Unit      125 m
Store to Research Lab           180 m

Number of Computers
Accounts              25
Research Lab          100
Store                 15
Packaging Unit        60

As a network expert, provide the best possible answer for the following queries: i) Suggest a cable layout of connections between the buildings. ii) Suggest the most suitable place (i.e. buildings) to house the server of this organization. The most suitable place/ building to house the server of this organization would be building Research Lab, as this building contains the maximum number of computers. iii) Suggest the placement of the following device with justification: a) Repeater b) Hub/Switch 1 a) For layout1, since the cabling distance between Accounts to Store is quite large, so a repeater would ideally be needed along their path to avoid loss of signals during the course of data flow in this route. For layout2, since the cabling distance between Store to Research Lab is quite large, so a repeater would ideally be placed. b) In both the layouts, a Hub/Switch each would be needed in all the buildings to interconnect the group of cables from the different computers in each building. iv) Suggest a system (hardware/software) to prevent unauthorized access to or from the network. 1 (iv) Firewall