SOLVED NATIONAL PABSAN KATHMANDU Pre-Qualifying Exam-2081

 

SOLVED NATIONAL PABSAN KATHMANDU

Pre-Qualifying Exam-2081

Class-X

FM-50

Sub-Opt, Computer Science

Time-2hrs

PM-17.5

 

"Group-A" [10 Marks]

 

1. Answer the following questions in one sentence.                       [6×1=6]

 

a. Define computer network.

Ans: Computer network is a group of two or more computers and devices connected to each other through wired or wireless media to exchange data and information and share hardware, software and other resources.

 

b. What is search engine?

Ans: A search engine is an online tool that helps users find information on the internet using keywords or phrases, and provide relevant results.

 

c. What is tuple in database?

Ans: A tuple is a row in a table which contains information about single items in a database.

 

d. Give name of any two RDBMS software.

Ans: MS-Access and Oracle

 

e. Define local variable.

Ans: A variable which is defined in a module and is not accessible to any other module is called local variable.

 

f. Write down any two features of C programming language.

Ans: Any two features of C programming language are:

·       Portability: C code can be compiled and executed on different systems with minimal modifications.

·       C is a case-sensitive programming language. It understands the capital alphabets and small alphabets as different values.

 

 

2. Write the appropriate technical terms for the following.                                            [2×1=2]

 

a. Networking devices use to regenerate the signal and transfer further. Repeater

b. Online postal service, E-mail

 

3. Write the full forms.                                                                                                         [2×1=2]

 

i. SIM – Subscriber Identity Module

ii. NOS – Network Operating System

 

"Group-B" [24 Marks]

 

4. Answer the following questions.                                                                                      [9×2=18]

 

a. What are the two advantages of ring topology over bus topology?

Ans: The two advantages of ring topology over bus topology are:

Ring topology manages data traffic more efficiently with technologies like token passing.

Ring topology supports equal data transmission opportunities for all devices.

 

b. Define hardware security. Write the importance of power protection device to protect the computer.

Ans: Hardware security refers to the protection of the physical components of a computer or electronic device from unauthorized access, theft, or damage.

The importance of power protection device to protect the computer is to prevent damage to the computer's hardware and data loss due to sudden power fluctuations.

 

c. What do you mean by Digital Citizenship? List its' two advantages.

Ans: Digital citizenship refers to the responsible and ethical use of technology and the internet which involves understanding, practicing, and promoting appropriate behavior when using digital tools and resources.

Any two advantages are:

It teaches users to protect personal information and avoid online risks like cyberbullying and scams.

Encourages creating a responsible and ethical online presence.

 

d. Define e-commerce. Give example of any two commercial sites in Nepal.

Ans: E-commerce refers to the buying and selling of goods and services over the internet.

Any two commercial sites in Nepal are: mucha and daraz.

e. List any two threats of using social media.

 

f. Define Form and Report.

Ans: Form is one of the MS-Access database objects which provides graphical interface to view, modify and add data in a table or multiple linked tables.

Report is one of the MS-Access database objects used to present information in an effective and organized format that is ready for printing.

 

g. Write down the advantages of database management system over traditional data storage system.

The advantages of database management system over traditional data storage system are:

a)     It reduces data redundancy which means duplication of data.

b)     It allows multiple users to access the same data simultaneously.

c)     Large volume of data can be stored and updated easily.

d)     It provides high security of data as well as maintains accurate database.

 

h. What is the difference of 'Allow Zero length' and 'required' field properties of MS-Access.

Ans: The "Allow Zero Length" property controls if empty strings are allowed, while the "Required" property ensures the field cannot be left null.

 

i. Define Query. List out its type.

Ans: Query is an object of database that is used to view, retrieve, change and analyze records from a table or multiple linked tables based on specified condition.

Its types are:

Select query and Action Query (update, delete, append  and make table query

 

5. Write the output of the following program.                                                                   [2]

 

DECLARE SUB series ()

CALL series

END

 

SUB series ()

i = 3

FOR c = 1T0 5

PRINT i *c^2;

NEXT c

END SUB

 

Dry Run

i	C=1 to 5	PRINT i *c^2;
3	1 to 5 yes	3x1^2 3x1 =3
	2 to 5 yes	3x2^2 3x4 =12
	3 to 5 yes	3x3^2 =3x9 27
	4 to 5 yes	3x4^2 =3x16 =48
	5 to 5 yes	3x5^2 3x25 =75
	6 to 5 no Loop exists

 

The output of the program is:

3  12  27  48  75

 

6. Re-write the given program after correcting the bugs. REM to find the factorial of a given number.

 

[2]

 

DECLARE FUNCTION FACTO (N$)

CLS

INPUT "Enter a number"; N

CALL FACTO (N)

END

 

FUNCTION FACTO ( )

F = 1

WHILE N = 0

F =F* N

N = N - 1

WEND

FACTO=F

END SUB

 

Debugged Program:

DECLARE FUNCTION FACTO (N)

CLS

INPUT "Enter a number"; N

PRINT FACTO (N)

END

 

FUNCTION FACTO (N)

F = 1

WHILE N < > 0

F =F* N

N = N - 1

WEND

FACTO=F

END FUNCTION

 

 

7. Study the given program and answer the given questions.[2]

 

DECLARE SUB SUM (N)

CLS

INPUT "Enter any number"; N

CALL SUM (N)

END

 

SUB SUM (N)

WHILE N > 0

R=N MOD 10

T = T + R

N =Ni10

WEND

PRINT "The Sum of individual digit is"; T

END SUB

 

Questions:

a) How many parameter(s) is used in the above program? List them.

Ans: 1 parameter is used in the above program.

 

b) Write the use of MOD in above program.

Ans: The MOD operator is used to calculate the remainder of a division operation between two numbers.

 

"Group-C" [16 Marks]

 

8. Convert/Calculate the following as per instructions [4×1=4]

 

i. (9876)10 into Binary

 

Divide by the base 2 to get the digits from the remainders:

Division by 2	Quotient	Remainder (Digit)
(9876)/2	4938	0
(4938)/2	2469	0
(2469)/2	1234	1
(1234)/2	617	0
(617)/2	308	1
(308)/2	154	0
(154)/2	77	0
(77)/2	38	1
(38)/2	19	0
(19)/2	9	1
(9)/2	4	1
(4)/2	2	0
(2)/2	1	0
(1)/2	0	1

= (10011010010100)₂

 

(9876)10 = (10011010010100)₂

 

 

ii. (2081)16 into octal

Converting hex to binary

6C₁₆ =

6 = 0110

C = 1100 = 1101100₂

1101100₂ 

Converting binary to octal

001 = 1

101 = 5

100 = 4

 

 (2081)16 = (154)₈

 

 

iii. 11010+10110

 

	1	1	0	1	0
+	1	0	1	1	0
1	1	0	0	0	0

 

11010+10110 = 110000

 

iv. 101110 ¸ 101

 

101)	1	0	1	1	1	0	(1001
	-1	0	1
	0	0	0	1	1	0
				1	0	1
				0	0	1

 

Q = 1001

R = 1

 

 

9. (a) Write a program to calculate area of a circle using SUB..... END SUB and perimeter of rectangle using FUNCTION... END FUNCTION.                                                              [4]

 

            DECLARE SUB AREA (R)

            DECLARE FUNCTION PER(L, B)

            CLS

            INPUT “Enter radius of circle”; R

            INPUT “Enter length of rectangle”; L

            INPUT “Enter breadth of rectangle”; B

            CALL AREA(R)

            PRINT “Perimeter of rectangle=”; PER(L,B)

            END

 

            SUB AREA(R)

            A= 22/7 * R ^ 2

            PRINT “Area of rectangle=”; A

            END SUB

 

            FUNCTION PERI(L, B)

            PERI = 2 * (L + B)

            END FUNCTION

 

b. A sequential file "detail.dat" contain Name, Age and mobile number of few persons. Write a QBASIC program to display the name of those persons who are eligible to cast the vote. [ Age must be 18 or above to cast the vote.]                                                                                                      [4]

 

OPEN “detail.dat” FOR INPUT AS #1

CLS

PRINT “Name of persons who are eligible to cast vote are”

WHILE NOT EOF(1)

INPUT  #1, N$, A, P

IF A>=18 THEN PRINT N$

WEND

CLOSE #1

END

 

10. Write a C program to test whether the given number is exactly divisible by 13 or not.

 

#include <stdio.h>

int main()

{

    int num;

    printf("Enter a number: ");

    scanf("%d", &num);

    if (num % 13 == 0)

{

        printf("The number %d is divisible by 13.\n", num);

    }

 else

{

        printf("The number %d is not divisible by 13.\n", num);

    }

    return 0;

}