a)  i)  Explain what is meant by the term volatile memory                                                            (1mark)

• Memory content is lost when the power is turned off

ii) What is normally stored in the non-volatile part of a computer’s main memory                       (1mark)

• The Computer’s BIOS

b) Explain why having cache memory can improve the performance of the CPU                         (2mks)

• Frequently used data/instructions are store in the cache; Meaning they don’t have to be fetched from the main memory;
• Data/instructions stored in the cache memory can be accessed faster (than data/instructions stored in the main memory) MAX 2

• RAID 10 is a combination of RAID 0 (zero) and RAID 1 (one)

• It is the use of proofing tools like spelling and grammar checkers and autocorrects to check whether a document has typographical or grammatical errors

Trojan (horse); a program which misleads the user into thinking it is another

piece of software which, when run, executes another program;

Spyware; a program which records data such as usernames and passwords on

a host system and forwards the information to a third party;

Adware; code embedded or attached to program files which will persistently

show adverts (that attempt to generate revenue);

Worm; code which will run autonomously and replicates itself on a host system;

Ransomware; a program that encrypts user’s data to make it unreadable until

they pay for the key;

Remote Access Tool (RAT); allows access to control and monitor a computer

from a remote network location;

Rootkit; malware that has managed to gain ‘root’ admin privileges;

Bots/Zombies; a program installed on a computer that performs a job for the

remote owner of the bot/zombie such as sending spam or sending web requests

to perform a DOS or attacking a computer system;

Scareware; malware that tells you something is wrong with your system in an

attempt to get you to make a purchase;

Keylogger; a program that monitors/records a user’s keystrokes in order to steal

passwords/confidential details;

A record showing who has accessed a computer system and what operations he or she has performed during a given period of time

• Developing training materials
• Training computer users
• Conducting ICT examinations
• Managing the learning and examination process
• Developing guidelines for using the computer lab
• Planning the course content
•  

• Portable
• Light
• Faster access speed
• No moving parts
• Efficient power consumption
• Durable
• Small physical size
• Large storage capacity

• Share peripherals/devices (e.g. printers, scanners)
• Communicate (e.g. email, instant messaging, play games)
• Share data (e.g. files/music/videos/backups on servers)
• Deploy/update applications
   
   

• data must be up to date
•  data can only be read/used for the purpose for which it was collected
• data must be adequate, relevant and not excessive
• data must be accurate
• data must be destroyed when no longer needed/don’t keep longer than necessary
• data user must register what data stored
• data must be used/collected fairly and lawfully
• data must be held securely
• data must be protected from accidental damage
• only authorised personnel can have access to the data
• fines are imposed for data mis-use
• data should not be passed on to a third party without permission
• a person can view data and have it changed/removed if incorrect

The booting process is the sequence of events that occur when a computer is turned on or restarted. It involves a series of steps that allow the computer's operating system to initialize and become functional. Here's a simplified explanation of what happens during the booting process:

1. Power-On Self-Test (POST): When the computer is powered on, the first thing it does is perform a Power-On Self-Test. During this step, the computer's hardware components, such as the CPU, memory, and storage devices, are checked for proper functioning. The POST verifies that all essential hardware components are present and operational.

2. Bootloader: Once the POST is completed, the computer looks for the bootloader. The bootloader is a small program stored in the computer's firmware or on the bootable device (such as the hard drive or a USB drive). It is responsible for loading the operating system.

3. Loading the Operating System: The bootloader locates the operating system's files and initiates the loading process. It may display a boot menu allowing the user to choose the operating system if multiple options are available. The selected operating system's core files are loaded into the computer's memory.

4. Kernel Initialization: The operating system's kernel, which is the central component responsible for managing system resources, is initialized. The kernel sets up essential components such as device drivers, memory management, and process management.

5. System Initialization: After the kernel is initialized, the operating system proceeds with system initialization. During this stage, various system services and processes are started, and hardware devices are initialized and configured. The operating system loads essential system files and prepares the environment for user interaction.

6. Login/Graphical Interface: Once the system initialization is complete, the user is presented with a login prompt or a graphical user interface (GUI). The user can then log in with their credentials or interact with the GUI to access the computer's functionalities.

• Main document
• Data source
• merged document

(a) Buffer

• temporary storage or memory which compensates for the difference speed of peripherals and the CPU

(b)batch processing

• processing doesn’t start until all data is collected
• JCL (any reference to Job Control Language)
• no need for user interaction
• processed all in one go
• done at “quiet” times
• e.g. billing, payroll, cheque processing

(c) e-commerce

• electronic commerce
• buying and selling products/services using the internet/computer networks

(d) simulation

• studying the behaviour of a system by using a model/mathematical representation
• results can be predicted
• e.g. flight (or other) simulator, modelling hazardous chemical process

(e) Email

• sending messages from one device to another using computer networks/Internet

• Refers to the scrambling of data into unreadable form before transmission over a telecommunication media  OR
• transformation of data from plaintext to ciphertext

Hard disk drive

• to hold the operating system/communication and applications software/ISP software
• for storing files/information/cookies on backing store

RAM

• for data, computer programs and operating instructions which are moved into it/downloaded for data currently in use

DVD writer

• Films/videos/pictures/music/multimedia data downloaded/purchased

Modem

• link/dial up/establish communication with the Internet
• Convert digital signals to analogue/audio tones (and vice versa) Which can travel across the telephone system

• Financial accounting
• Prediction and forecasting
• Inventory keeping
• Budgeting
• Keeping records

(i) Jobs collected together for processing at a later time
(ii) Output produced quickly enough to affect the next input
(iii) User has direct contact with the processor
(iv) User cannot communicate directly with the processor

• Fibre optic cable would be used because it has a higher bandwidth, allowing faster communication in the main part of the network. It is also more secure as it cannot be tapped.
• Firewalls filter the data in and out of a network. Each packet is examined against the filter rules and if a packet is flagged, it is dropped. Only data packets that satisfy the filter rules are allowed through the firewall, thus providing a layer of security for the network.
• A satellite system would be better as it does not rely on wifi, cellular etc. It is not subject to interference and is reliable in remote conditions
• Radio-frequency identification (RFID) uses electromagnetic fields to automatically identify and track tags attached to objects. An RFID system consists of a tiny radio transponder, a radio receiver and transmitter. When triggered by an electromagnetic interrogation pulse from a nearby RFID reader device, the tag transmits digital data, usually an identifying inventory number, back to the reader. This number can be used to track inventory goods..

(a)Explain why programmers prefer to represent instruction in hexadecimal rather than in binary

• A larger number of values can be represented using fewer characters.
• the shorter length and more characters make the pattern easier to read and understand
• recognisable character codes can be used for debugging

(b) Give two other uses of hexadecimal

• HMTL color codes representing RGB spectrum in the web development
• representation of MAC and IP addresses allowing a larger combination of unique addresses

SECTION A (40 MARKS)

1.Describe the purpose of each of the following computer functional units:    (2mks)

    a) Control

    b) Storage

2.Explain how each of the following would affect the suitability of a room for use as a computer room: (2mks)

a) Burglar proofed door

b)Availability of taps and sinks in the room

3.State three data representation codes used in computers       (3mks)

4.State two types of documentation in program development and give the purpose of each.     (4mks)

5.Suppose a 5 element array A contains the values 9, 12, 17, 7 and 20.  Find the value in A after executing the loop below:

            Repeat for k = 1 to 4

            Set A [k +1]: = A [k]

                        [End of loop]            (3mks)

6.State any three activities that occur in a program compilation process  (3mks)

7.The formula = k20 + P$ 18 was typed in cell L21 and then copied to cell M24 of a spreadsheet. Write the formula as it appears in cell M24.(2mks)

8.State two ways in which a computer may be used in the efficient running of a hospital (2mks)

9.List three disadvantages of using the traditional file management method          (3mks)

10.Give one disadvantage of a single processor multi-user system    (1mk)

11. List three differences between a micro-computer and a super-computer.         (3mks)

12.State and explain two reasons why word processing is one of the most common applications of many computer users.   (2mks)

13. write- 1 in twos complement notation in byte form                                        (4mks)

14.Explain the following input/output terms as used in computer systems. Give an example for each        (4mks)

  a) Read

  b) Write

15.State two disadvantages of networking.

SECTION B (60 MKS)

Answer question 16 and any other three questions from this section.

16.The following flowchart can be used to list the odd numbers between 0 and 100

a)Write a program segment for the flowchart using a high level language.  (7mks)

b)What would be the output from the flowchart if the statement in the decision box is changed to:  (3 mks)

i)          Odd = 100

ii)         Odd< 100

iii)        Odd> 100

c)  Modify the flowchart so that it prints only the sum of the odd number between 0 and 100  (5mks)

17.a)  List five precautions that can be taken to protect data stored in diskettes   (5mks)

b)State and explain two precautions that can be taken to help recover data lost through accidental erasure. (4mks)

   c) Describe each of the following data processing methods:    (6mks)

   i) Batch processing

   ii) Distributed processing

   iii) Multiprogramming

18. a)  i)  What is a computer keyboard?      (1 mk)

           ii)  ist four types of keys found on a computer keyboard.  Give an example of each(4mks)

     b) Give four differences between present day’s computers and the older generation of computers   (4mks)

     c)   i) State three advantages and one disadvantage of using a laser printer.  (4mks)

           ii) Distinguish between a line printer and a page printer             (2mks)

19  a) Identity three public Universities and three National Polytechnics in Kenya where further computer training is offered. In case, state the highest level of qualification that can be acquired in computer training. (6 mks)

b) Distinguish between “Job replacement” and “Job displacement” in reference to computerization.  (2mks)

c) Give four reasons why a firm may decide to computerize its operations.   (4mks)

d) An individual has a right to demand a guarantee of privacy of personal information stored on a computer.Give three such types of information.  (3mks)

20. a)  Give three comparisons of the traditional file management method of typing a document on a typewriter against using a word processor.     (6mks)

      b)  i) Define the term spreadsheet (1 mk)

            ii) Give two examples of spreadsheet packages available in the market today        (2mks)

      c) Explain the following terms as used in a spreadsheet:

             i)  What if …analysis         (2 mks)

             ii) Cell                (1 mk)

             iii) Formula  (1mk)

             iv)  Pie chart                                                                      (2 mks)