SOLVED PABSON Kathmandu SEE COMPUTER SCIENCE 2081 FIRST TERMINAL EXAMINATION-2081 [B]

 

SOLVED PABSON Kathmandu  SEE COMPUTER SCIENCE 2081 FIRST TERMINAL EXAMINATION-2081[B]

PABSON Kathmandu

FIRST TERMINAL EXAMINATION-2081

 

Subject: Opt. II Computer Science             Full Marks: 50

Class: 10                                                         Time: 2 hrs.

Candidates are required to answer the questions in their own way words as far as practicable. Figures in the margin indicate the full marks.

 

Attempt all questions.

 

Group ‘A'

 

1. Answer the following questions in one sentence:          (6´1=6)

 

a) What is an uploading?

      Upload is the process of transferring files or data from user’s computer or device to a remote server or another device.

 

b) Write few popular ISP's of Nepal.

      Mercantile and Wlink, are few popular ISP’s of Nepal

 

c) List any two examples of cybercrimes.

      Ay two cybercrimes are phishing and hacking.

 

d) List any two services of internet.

      Any two services of internet are E-Mail and E-Commerce.

 

e) What is local variable in QBASIC?

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

 

f)   Which statement is used to call FUNCTION and SUB procedure?

      A SUB procedure is called using the CALL statement.

      A FUNCTION procedure is called using its name in an expression or an assignment statement.

 

 

2. Write appropriate technical term for the following:    (2´1=2)

a) A group of computers that functions both as a client and server.

      Peer to Peer Network

 

b) The unauthorized duplication and use of computer software.

      Software Piracy

 

3. Write the full form of the following:                               (2´1=2)

a) URL – Uniform Resource Locator               

b) ICT    - Information and Communication Technology

 

Group ‘B'

 

4. Answer the following questions:                                     (9´2=18)

 

a)   Write any two advantages and disadvantages of computer network.

Any two advantages of computer network are:

v Users can share resources like hardware (printers) and software (applications) across the network.

v Allows users to easily share and access files from different computers.

Any two disadvantages of computer network are:

 

v Networks can be hacked, leading to loss or theft of important data.

v Keeping a network running smoothly can be expensive and requires regular updates.

 

b) What is network connecting device? Write any two of them.

      A network connecting device is hardware that connects computers and devices to enable communication, data sharing, and resource access. Any two network connecting devices are router and switch.

 

 

 

 

c) What is data communication mode? List its type.

Data transmission mode is the way of transmission of data from one location to another.

Its types are:

Simplex mode is the transmission of data and information that takes place in only one direction.

Half-duplex is the transmission of data and information that flows in both directions but only one direction at a time

Full duplex mode is the transmission of data and information that flows in both direction simultaneously on the transmission path

 

d) What is internet? Write any one negative impact of internet.

The Internet is a global network of connected devices enabling communication, information sharing, and access to online services.

Any one negative impact of internet is:

Personal information can be exposed to hackers or misused by online services.

 

e) What is cyber law? Why is it important?

The law which governs the legal issues in the cyber space regarding the internet or WWW for digital data processing and transaction is called cyber law.

The importance of cyber law is that it controls cyber-crime and misuse of computer.

 

f) What is hacking? What is the purpose of hacking?

Hacking is the act of gaining unauthorized access to computer systems, networks, or devices to manipulate, steal, or disrupt data.

The purpose of hacking is to steal personal or sensitive information, damage systems, or disrupt services.

 

g) What is digital signature? Why is it necessary in E-commerce?

Digital signature is a security mechanism system used on the internet for data and information transaction by attaching a code at the end of the electronic message that confirms the authenticity of sent message.

It is necessary in E-commerce to provide legal framework to facilitate and safeguard electronic transaction in the electronic media.

 

h) Differentiate between SUB and FUNCTION procedure.

Sub procedure	Function procedure
Sub procedure name cannot have type declaration sign	Function procedure name not have type declaration sign
Sub procedure does not return value to calling module	Function procedure returns value to the calling module

 

 

i) Define 'formal parameter' and 'actual parameter'.

Formal parameter are variables which are used to specify or declare types of data to be passed to the procedure either sub or function.

Actual parameter is argument which is used to pass real value or data to the procedure.

 

5.   Write down the output of the given program. \Show with dry run in table.                                                                              (2)

DECLARE SUB SERU ( )

CLS

CALL SERU

END

SUB SERU ( )

X=2

C=1

WHILE C<=10

S=X^C

PRINT S;

C=C+1

WEND

END SUB

 

 

 

 

      Dry Run

X	C	C<=10	S=X^C	PRINT S;	C=C+1
2	1	1<=10 Yes	2^1=2	2	1+1=2
	2	2<=10 Yes	2^2=4	4	2+1=3
	3	3<=10 Yes	2^3=8	8	3+1=4
	4	4<=10 Yes	2^4=16	16	4+1=5
	5	5<=10 Yes	2^5=32	32	5+1=6
	6	6<=10 Yes	2^6=64	64	6+1=7
	7	7<=10 Yes	2^7=128	128	7+1=8
	8	8<=10 Yes	2^8=256	256	8+1=9
	9	9<=10 Yes	2^9=512	512	9+1=10
	10	10<=10 Yes	2^10=1024	1024	10+1=11
	11	11<=10 No Loop Exits

The output of the program is

2  4  8  16  32  64  128  256  512  1024

 

6.   Re-write the given program after correcting the bugs:          (2)

      CREATE FUNCTION SQUA(A)

      REM to print square of a number

      CLS

      Get "Enter a number"; A

      Call SQUA(A)

      END

FUNCTION SQUA(A)

ANS=A^2

8ANS=SQUA

END FUNCTION

 

      Debugged Program

      DECLARE FUNCTION SQUA(A)

      REM to print square of a number

      CLS

      INPUT "Enter a number"; A

      PRINT SQUA(A)

      END

FUNCTION SQUA(A)

ANS=A^2

SQUA = ANS

END FUNCTION

 

7. Study the following program and answer the given questions:

                                                                                                (2´1=2)

DECLARE SUB RESULT(A$)

      A$="COMPUTER"

CALL RESULT(A$)

END

SUB RESULT(A$)

FOR I= 1 TO LEN(A$) STEP 2

X$=MID$(A$,C, I )

PRINT X$;

NEXT I

END SUB

 

Questions:

a) List the library functions used in above program.

      The library functions used in above program are

LEN ( ) and MID$ ( )

 

b) How many times loop executes in above program.

      The loop executes four times in above program.

 

Group ‘C'

 

Long question Answers:                                                       (4´4=16)

8.  Convert / calculate as per the instruction:

i) (111101 - 1101) + (11011)

	1	1	1	1	0	1
		-	1	1	0	1
0	1	1	0	0	0	0
	+	1	1	0	1	1
1	0	0	1	0	1	1

(111101 - 1101) + (11011) = (1001011)

 

 

 

ii) (110111  11) + (1101)

 

11)	1	1	0	1	1	1	(10010
	1	1
		0	0	1	1
				1	1
				0	0
					1
					1

 

Q = 10010

R = 1

 

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

 

(110111  11) + (1101) = 11111

 

 

iii) (129 )₁₀  into binary    

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

Division by 2	Quotient	Remainder (Digit)
(129)/2	64	1
(64)/2	32	0
(32)/2	16	0
(16)/2	8	0
(8)/2	4	0
(4)/2	2	0
(2)/2	1	0
(1)/2	0	1

= (10000001)₂

 

(129 )₁₀  = (10000001)₂

     

     

 

iv) ( DA3 )₁₆ into decimal

(DA3 )₁₆

= (13 × 16²) + (10 × 16¹) + (3 × 16⁰)

=13 x 256 + 10 x 16 + 3 x 1

=3328 + 160 + 3

=3491

 

( DA3 )₁₆ =(3491)₁₀

 

 

9.   a)   Write a program in QBASIC that allow user to enter radius of a circle. Create user define FUNCTION…END FUNCTION to find area of circle and SUB…END SUB to find volume of a cylinder.

            DECLARE FUNCTION AREA(R)

            DECLARE SUB VOL(R)

            CLS
INPUT “Enter Radius”; R

            INPUT “Enter Height”; H

            PRINT “Area of circle”; AREA(R)

            CALL VOL(R, H)

            END

 

            FUNCTION AREA(R)

            A = 22/7 * R ^ 2

            PRINT “Area if circle=”; A

            END FUNCTION

 

            SUB VOL(R)

            V = 22/7 * R ^ 2 * H

            PRINT “Volume of cylinder=”; V

            END SUB

 

 

 

 

 

 

 

      b) WAP to reverse a number using SUB…END SUB.         

DECLARE SUB REV (N)

CLS

INPUT "ENTER ANY NUMBER"; N

CALL REV (N)

END

 

SUB REV (N)

S = 0

WHILE N < > 0

R = N MOD 10

S = S * 10 + R

N = N \ 10

WEND

PRINT "REVERSED DIGITS="; S

END SUB

10. Write FUNCTION program to check whether the supplied number is divisible by 5 or not.

DECLARE FUNCTION CHECK$ (N)

INPUT “ENTER ANY NUMBER”; N

PRINT “THE NUMBER IS”; CHECK$ (N)

END

 

FUNCTION CHECK$ (N)

IF N MOD 5 = 0 THEN

CHECK$ = “Divisible by 5”

ELSE

CHECK$ = “Not divisible by 5”

END IF

END FUNCTION

 

Or

 

 

 

 

 

 

 

Write a program to count the occurrence of letter 'a' in the supplied string using SUB…END SUB.

DECLARE SUB COUNT (S$)

CLS

INPUT "ENTER ANY STRING"; S$

CALL COUNT(S$)

END

 

SUB COUNT (S$)

AC = 0

FOR I = 1 TO LEN(S$)

B$ = MID$(S$, I, 1)

C$ = UCASE$(B$)

IF C$ = "A" THEN AC = AC + 1

NEXT I

PRINT "TOTAL NO. OF LETTER E = "; AC

END SUB

 

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