ICT Fundamentals 4 — Questions and Answers
Question 1: What is the hexadecimal equivalent of the decimal number 255?
- EE
- FE
- FF (Correct answer)
- EF
Correct answer: FF
Decimal 255 equals FF in hexadecimal, since F represents 15 and 15×16 + 15 = 255.
Question 2: Which layer of the OSI model is responsible for end-to-end communication and error recovery?
- Network layer
- Transport layer (Correct answer)
- Session layer
- Data Link layer
Correct answer: Transport layer
The Transport layer (Layer 4) of the OSI model handles end-to-end communication, error recovery, and data flow control.
Question 3: What distinguishes RAM from ROM?
- RAM is permanent; ROM is temporary
- RAM is volatile; ROM is non-volatile (Correct answer)
- RAM is slower than ROM
- RAM stores the BIOS; ROM stores user data
Correct answer: RAM is volatile; ROM is non-volatile
RAM is volatile memory that loses its data when power is removed, while ROM is non-volatile and retains data without power.
Question 4: Which type of network topology connects all devices to a single central cable?
- Star topology
- Ring topology
- Bus topology (Correct answer)
- Mesh topology
Correct answer: Bus topology
Bus topology connects all devices to a single backbone cable, with terminators at each end to prevent signal reflection.
Question 5: What is 'phishing' in the context of cybersecurity?
- Scanning a network for open ports
- Encrypting files for ransom
- Tricking users into revealing sensitive information (Correct answer)
- Overloading a server with requests
Correct answer: Tricking users into revealing sensitive information
Phishing is a social engineering attack that tricks users into revealing sensitive data like passwords through deceptive emails or websites.
Question 6: Which file format is most commonly used for lossy image compression?
- PNG
- BMP
- GIF
- JPEG (Correct answer)
Correct answer: JPEG
JPEG uses lossy compression, which reduces file size by permanently discarding some image data to achieve smaller file sizes.
Question 7: What is the role of DNS in internet communication?
- Encrypts web traffic
- Translates domain names to IP addresses (Correct answer)
- Assigns MAC addresses to devices
- Manages email routing
Correct answer: Translates domain names to IP addresses
DNS (Domain Name System) translates human-readable domain names like www.example.com into numeric IP addresses computers use.
ICT Fundamentals 4
What is the hexadecimal equivalent of the decimal number 255?