EXERCISE SOLUTION - GOVENRNMENT BOOK COMPUTER SCIENCE 2083

 EXERCISE SOLUTION - GOVENRNMENT BOOK COMPUTER SCIENCE 2083

1. Write the full forms of the following abbreviations:

1. Full Forms

a) DSL – Digital Subscriber Line
b) bps – Bits Per Second
c) LAN – Local Area Network
d) TCP/IP – Transmission Control Protocol / Internet Protocol
e) IPv6 – Internet Protocol Version 6
f) ISP – Internet Service Provider
g) RFID – Radio Frequency Identification
h) CAT6 – Category 6 Cable
i) NCP – Network Control Protocol
j) DNS – Domain Name System

 

2. Choose the correct answer from the given options:

2. Choose the Correct Answer from the Given Options

i. Which of the following is a broadband Internet connection?

a) DSL
b) Fiber optic
c) Cable internet
d) All of the above

Answer: d) All of the above

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ii. What is throughput?

a) Theoretical speed of a network
b) Actual data transferred in a given time
c) Length of a network cable
d) Number of users

Answer: b) Actual data transferred in a given time

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iii. What is a data packet?

a) A physical network device
b) A unit of data sent over a network
c) A type of wireless method
d) A security tool

Answer: b) A unit of data sent over a network

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iv. Which of the following is a type of bounded (guided) media?

a) Fiber optic
b) Infrared
c) Microwave
d) Laser

Answer: a) Fiber optic

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v. Which term refers to sending data from Earth to a satellite?

a) Downlink
b) Modulate
c) Uplink
d) Download

Answer: c) Uplink

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vi. What is the RJ45 connector mainly used for?

a) USB connections
b) Telephone lines
c) Ethernet networking
d) Fiber optics

Answer: c) Ethernet networking

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vii. What is the connection pattern of computers in a network called?

a) Protocol
b) Topology
c) Twisted pair
d) Structure

Answer: b) Topology

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viii. Which topology uses a hub to connect all devices?

a) Ring topology
b) Bus topology
c) Star topology
d) Hybrid topology

Answer: c) Star topology

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ix. What type of network connects LANs over large areas?

a) PAN
b) MAN
c) WAN
d) CAN

Answer: c) WAN

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x. Which of the following are Internet services?

a) IRC
b) Telnet
c) Email
d) All of the above

Answer: d) All of the above

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xi. Which protocol is used to transfer files between computers?

a) FAQ
b) IRC
c) FTP
d) TPF

Answer: c) FTP

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xii. What is the length of an IPv4 address?

a) 16 bits
b) 32 bits
c) 64 bits
d) 128 bits

Answer: b) 32 bits

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xiii. What does an IP address identify?

a) A software
b) A network cable
c) A specific device on the network
d) A computer brand

Answer: c) A specific device on the network

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xiv. Which protocol is commonly used for sending emails?

a) HTTP
b) FTP
c) SMTP
d) DHCP

Answer: c) SMTP

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xv. Which device strengthens weak network signals for long distances?

a) Switch
b) Router
c) Repeater
d) Bridge

Answer: c) Repeater

Answer Key

i-d, ii-b, iii-b, iv-a, v-c, vi-c, vii-b, viii-c, ix-c, x-d, xi-c, xii-b, xiii-c, xiv-c, xv-c 📡💻📚

 

3. Short Answer Questions (2 Marks Each)

a) What is broadband? How is it different from dial-up connections?

Answer:
Broadband is a high-speed Internet connection that provides continuous access to the Internet. Unlike dial-up connections, broadband is much faster and does not require a telephone line to be occupied while using the Internet.

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b) Define bandwidth. How is it measured?

Answer:
Bandwidth is the maximum amount of data that can be transmitted through a network connection in a given period of time. It is usually measured in bits per second (bps), such as Kbps, Mbps, or Gbps.

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c) What is a data packet in networking?

Answer:
A data packet is a small unit of data transmitted over a network. Large messages are divided into packets, which travel separately and are reassembled at the destination.

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d) What is frequency in telecommunications?

Answer:
Frequency is the number of times a signal wave repeats in one second. It is measured in Hertz (Hz) and determines the transmission characteristics of communication signals.

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e) What is the function of a repeater?

Answer:
A repeater is a networking device that receives weak signals, amplifies or regenerates them, and retransmits them. It helps extend the communication distance of a network.

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f) What is a computer network? How is it useful?

Answer:
A computer network is a collection of interconnected computers and devices that can communicate and share resources. It is useful for sharing files, printers, Internet connections, and information efficiently.

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g) Why is wireless communication becoming more popular today?

Answer:
Wireless communication is becoming more popular because it provides mobility, flexibility, and easy installation without requiring physical cables. It also allows users to access networks from different locations.

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h) Describe the RJ45 connector. Where is it commonly used?

Answer:
RJ45 is an 8-pin connector used with Ethernet cables for wired network communication. It is commonly used in Local Area Networks (LANs) to connect computers, switches, routers, and other network devices.

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i) What is a media converter? Mention its main function.

Answer:
A media converter is a networking device that converts one type of transmission media into another. Its main function is to connect copper-based Ethernet networks with fiber optic networks.

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j) What is the difference between bandwidth and throughput?

Answer:
Bandwidth is the maximum data transfer capacity of a network, whereas throughput is the actual amount of data successfully transferred in a given time. Throughput is usually lower than bandwidth due to network conditions.

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k) How does Wi-Fi transmit data without cables?

Answer:
Wi-Fi transmits data using radio waves between wireless devices and an access point or router. This enables communication without the need for physical network cables.

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l) How does data travel from one computer to another in a network?

Answer:
Data is divided into packets and sent through networking devices such as switches and routers. The packets travel across the network and are reassembled when they reach the destination computer.

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m) How does data flow in a ring topology?

Answer:
In a ring topology, each device is connected to two neighboring devices, forming a circular path. Data travels around the ring in one direction until it reaches the intended destination.

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n) Mention one real-life use of satellite communication.

Answer:
One real-life use of satellite communication is satellite television broadcasting, where television signals are transmitted from satellites to viewers over large geographical areas.

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o) List two types of communication media and give one example of each.

Answer:

Communication Media	Example
Guided (Bounded) Media	Fiber Optic Cable
Unguided (Unbounded) Media	Radio Waves

These media are used to transmit data between devices in a communication network. 📡💻📚

 

4. Long Answer Questions (4 Marks Each)

i. What is communication media?

Answer:
Communication media refers to the channel or medium through which data and information are transmitted from one device to another in a network. It acts as a path for communication between the sender and receiver.

Communication media is mainly classified into two types:

1. Guided (Bounded) Media: Uses physical cables such as twisted pair cable, coaxial cable, and fiber optic cable.
2. Unguided (Unbounded) Media: Uses wireless signals such as radio waves, microwaves, and infrared waves.

Communication media plays a vital role in data transmission and network connectivity.

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ii. Differentiate between LAN and MAN.

LAN (Local Area Network)	MAN (Metropolitan Area Network)
Covers a small geographical area.	Covers a city or metropolitan area.
Used within a room, building, or campus.	Connects multiple LANs across a city.
Ownership is usually private.	May be owned by government or service providers.
Less expensive to set up.	More expensive to set up.
Example: School computer lab.	Example: City-wide cable network.

Conclusion: LAN is suitable for small areas, whereas MAN is suitable for connecting networks across a city.

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iii. Explain the differences between client-server and peer-to-peer network architectures.

Client-Server Network	Peer-to-Peer Network
Has a dedicated server.	No dedicated server.
Centralized management.	Decentralized management.
More secure.	Less secure.
Suitable for large organizations.	Suitable for small networks.
Higher setup cost.	Lower setup cost.

Conclusion: Client-server networks provide better security and management, while peer-to-peer networks are simple and cost-effective for small environments.

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iv. Suppose your school wants to set up a network in three separate buildings. What type of network should be used? Justify your answer.

Answer:
A MAN (Metropolitan Area Network) should be used to connect the three school buildings if they are located within the same city or nearby area.

A MAN can connect multiple LANs located in different buildings. It enables students, teachers, and administrators to communicate efficiently and share files and resources across all buildings. Internet access can also be shared through a central connection.

Using a MAN reduces communication costs, improves resource sharing, and ensures smooth network management throughout the school.

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v. Create a network model for your home that includes three PCs, one printer, and one mobile device connected to the internet.

Answer:

Network Layout

Internet
    |
 Router/Wi-Fi
    |
  Switch
 /  |  \
PC1 PC2 PC3
    |
 Printer

Mobile Device
     |
   Wi-Fi

Description

• A router connects the home network to the Internet.
• A switch connects the three PCs and printer using Ethernet cables.
• The mobile device connects wirelessly through Wi-Fi.
• The router manages Internet access and communication among all devices.

This design provides reliable wired connections for PCs and convenient wireless access for mobile devices.

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vi. Which network type would be more suitable for a small office: client-server or peer-to-peer? Justify your answer.

Answer:
A client-server network is more suitable for a small office.

It provides centralized management, better security, and easier backup of important data. Employees can access shared resources through the server while administrators can control user permissions.

Although the setup cost is higher than a peer-to-peer network, it offers better scalability, security, and management as the office grows.

Therefore, a client-server network is the preferred choice for a professional office environment.

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vii. Design a simple layout for a school computer lab network using at least one switch, 10 computers, and internet access.

Answer:

Network Layout

Internet
    |
 Router
    |
 Switch
 | | | | | | | | | |
PC1 PC2 PC3 PC4 PC5
PC6 PC7 PC8 PC9 PC10

Explanation

• The router connects the lab to the Internet.
• A switch connects all 10 computers.
• Ethernet cables are used to connect computers to the switch.
• The switch forwards data only to the intended device, improving efficiency.
• All computers can share files, printers, and Internet access through the network.

This design is simple, cost-effective, and suitable for a school computer laboratory. 📡💻🏫

 

SOLVED SEE COMPUTER SCIENCE 2082

 

SOLVED SEE COMPUTER SCIENCE 2082

 

SOLVED SEE COMPUTER SCIENCE 2082

 

Group 'A' (Very Short Answer Questions)

1. Answer the following questions in one sentence:

(a) What is transmission media?

Transmission media is a channel or path through which data and information are transmitted between connected devices in a network environment is called communication media.

(b) What is mobile commerce?

M-commerce refers to the buying and selling of goods and services through mobile devices like smartphones and tablets.

(c) Why Primary key is used in MS-Access?

A primary key is used in MS access because it reduces and control duplication of the record in a table, sets the relationship between tables and identifies each record of a table uniquely.

(d) Which data type is suitable to store date of admission of student while designing table structure in MS-Access?

The Date/Time data type is most suitable to store date of admission of student while designing table structure in MS-Access.

(e) What is modular programming?

Modular programming is a technique which divides program into many small logical, manageable and functional modules or blocks

(f) Write any two logical operators of 'C' language.

The two logical operators are && (AND) and || (OR).

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2. Write appropriate technical term for the following:

(a) A program that can disinfect virus from a file: Antivirus

(b) An artificial environment created by a computer system that appears real: Virtual Reality (VR)

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3. Write the full form of the following:

(a) LAN: Local Area Network

(b) URL: Uniform Resource Locator

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Group 'B' (Short Answer Questions)

4. (a) Mention any two difference between Client/Server and Peer-to-Peer Architecture of the computer network.

Client-Server Network	Peer to Peer Network
In a client-server network, powerful computers called servers provide resources and services, while other computers, known as clients, access these resources and services.	In a peer-to-peer network, all computers have equal roles and can both provide and request resources without a centralized server.
Security and data management are handled by the server. Network administrator manages and enforces security policies.	Security is managed individually on each peer. Each peer is responsible for its own security and data.

 

(b) Write any two opportunities and two threats of social media

Opportunities of using social media

Networking: Connect globally, build relationships, and join communities.

Information Sharing: Quickly access and share news and educational content.

Threats of using social media

Privacy Risks: Personal information can be exposed or misused.

Cyberbullying: Harassment or bullying through online interactions.

(c) Write the importance of backup in data and software security:

The importance of backup in data and software security is to keep copies of important files and data in a safe place. If computer crashes or accidentally deleted something, we can use these copies to restore our information and avoid losing important work or personal files.

 

 

(d) What is e-banking? Write its two advantages.

E-banking is a digital banking system that allows customers to perform financial transactions and manage their accounts online via the internet or mobile apps, eliminating the need to visit a physical bank branch.

Two advantages of e-banking:

24/7 access to banking services and convenience of performing transactions from home.

(e) What is IoT? Write any two importance of it.

Internet of Things (IoT) refers to a network of interconnected physical devices that can collect and exchange data over the internet without requiring human intervention.

Any two importance of Internet of Things (IoT) are

v It reduces the human effort, so it saves a lot of time. 

v Information is easily accessible from any place at any time on any device. 

(f) Write any four advantages of DBMS.

Four advantages of DBMS:

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.

(g) Which data types are suitable while designing table structure to store information about student’s name, Roll No., Address and Date of Birth in MS-Access 

Four data types for Student Table (Name, Roll No, Address, DOB):

1. Name: Short Text
2. Roll No: Number
3. Address: Short Text / Long Text
4. Date of Birth: Date/Time

(h)What is select query? Write the function of action query.

Select query is a type of query which is used to select and display the relevant data from the database.

The function of action query is to makes changes to or removes many records in just one operation.

(i) Define report. Why it is necessary to create a report in DBMS?

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

It is necessary to create a report in DBMS to present data from one or more tables in a formatted and organized manner, allowing users to easily view and analyze the information.

5. Write the output of the given program. Show them in a dry run table.

DECLARE SUB Series (A)

CLS

A = 5

CALL Series (A)

END

 

SUB Series (A)

FOR K = 1 TO 5

    PRINT A;

    A = A * 2

NEXT K

END SUB

 

Dry Run Table

Iteration (K)	Initial Value of A	Action (PRINT A;)	New Value (A = A * 2)
1	5	5	10
2	10	10	20
3	20	20	40
4	40	40	80
5	80	80	160

 

The output of the program is:

5  10  20  40  80

6. Rewrite the given program after correcting the bugs.

 

REM to add record in a existing file

CLS

OPEN "See.dat" FOR OUTPUT AS #2

BB:

INPUT "Enter the Name"; N$

INPUT "Enter the Address"; A$

INPUT "Enter the Class"; C

INPUT #2, N$, A$, C             

INPUT "More record "; Y$

IF UCASE (Y$) = "Y" THEN GOTO BB

CLOSE “see.dat”                        

END

 

 

 

Debugged Program

 

REM to add record in a existing file

CLS

OPEN "See.dat" FOR APPEND AS #2

BB:

INPUT "Enter the Name"; N$

INPUT "Enter the Address"; A$

INPUT "Enter the Class"; C

WRITE #2, N$, A$, C             

INPUT "More record"; Y$

IF UCASE$(Y$) = "Y" THEN GOTO BB

CLOSE #2                        

END

 

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

DECLARE FUNCTION LongestName$ (Z$)

DIM SHARED A$, B$, C$

CLS

READ A$, B$, C$

DATA "NEPAL", "BANGLADESH", "BHUTAN"

PRINT LongestName$(Z$)

END

 

FUNCTION LongestName$ (Z$)

    L$ = A$

    IF LEN(B$) > LEN(L$) THEN

        L$ = B$

    ELSEIF LEN(C$) > LEN(L$) THEN

        L$ = C$

    END IF

    LongestName$ = L$

END FUNCTION

 

a) Write the Global variables used in the above program.

The global variables in this program are A$, B$, and C$

(b) Why is the $ (dollar) sign used after the function name?

The $ sign is used after the function name (LongestName$) to indicate that the function will return a string value (text) rather than a numeric value.

 

8. Number System

i) (1011101)_2 = (135)8

ii) (188)_{10} = (BC)16

iii) (101)_2 \times (110)2 = (11110)2

iv) (111011)_2 \div (101)_2 = {Quotient: } (1011)2, { Remainder: } (100)2

 

 

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9. QBASIC Programming

a. Write a program to ask three numbers from a user and find their sum using Sub procedure and find the average of those numbers using Function procedure.

 

DECLARE SUB SUM (A, B, C)

DECLARE FUNCTION AVG (A, B, C)

CLS

INPUT "Enter three numbers: ", X, Y, Z

CALL SUM(X, Y, Z)

PRINT "Average of numbers is: "; AVG(X, Y, Z)

END

 

SUB SUM (A, B, C)

    S = A + B + C

    PRINT "Sum of numbers is: "; S

END SUB

 

FUNCTION AVG (A, B, C)

    AVG = (A + B + C) / 3

END FUNCTION

 

b. Write a program to store Roll No, Name, Class, Date of Birth and Address of students in data file "STUDETN.TXT". The program allows the users to input more data as many times as they need.

CLS

OPEN "STUDENT.TXT" FOR OUTPUT AS #1

DO

    INPUT "Enter Roll No: ", R

    INPUT "Enter Name: ", N$

    INPUT "Enter Class: ", C

    INPUT "Enter Date of Birth: ", D$

    INPUT "Enter Address: ", AD$

    WRITE #1, R, N$, C, D$, AD$

    INPUT "Do you want to add more data? (Y/N): ", CH$

LOOP WHILE UCASE$(CH$) = "Y"

CLOSE #1

END

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10. Write a program in 'C' language that checks whether the given number is Positive or Negative.

 

#include <stdio.h>

 

int main() {

    int num;

    printf("Enter a number: ");

    scanf("%d", &num);

   

    if (num > 0) {

        printf("%d is Positive.", num);

    } else if (num < 0) {

        printf("%d is Negative.", num);

    }

    return 0;

}

 

Write a program using 'C' language to display the series 100, 95, 90, 85, 80 ..... up to 10th term.C

#include <stdio.h>

 

int main() {

    int a = 100;

    int i;

    for (i = 1; i <= 10; i++) {

        printf("%d ", a);

        a = a - 5;

    }

    return 0;

}