A computer system refers to computer components that collectively function as a single unit to achieve the desired goal. It can also be defined as a collection of hardware, software, and liveware that work together to receive, process, and manage data

• connects different networks
• transfer data packets from source to destination
• allow hosts on different networks to communicate

Optical Mark Recognition; Optical Character Recognition; Magnetic Ink Character Recognition ; Optical Bar Recognition

Giving answers as readers is also acceptable, that is, Optical Character Readers, Magnetic Ink Character Readers; Optical Mark Readers

• An instruction is retrieved from the memory
• The instruction is decoded
• The instruction is executed
• the program counter is incremented

• an attribute/combination of attributes chosen to ensure that the records in a table are unique

SECTION A (40 MARKS)

ANSWER ALL THE QUESTIONS IN THIS SECTION

1.Compare the two types of diskettes used in microcomputers in terms of physical size and densities.    (2mks)

2.Why is it necessary to have a UPS in a computer laboratory?  (2mks)

3 a) Explain what is meant by batch processing   (1mk)

   b) Give one advantage and one disadvantage of batch processing ( 2mks)

4. List any four high level programming languages  (2mks)

5.A 3 by 4 matrix M is to be added to another 3 by 4 matrix array N so as to give a third 3 by 4 matrix array P.  Using a high level programming language, write a program segment that assigns the sum of M and N to P.(4mks)

6. The first column in the table below contains the formulae as stored into the cell F10 of a spreadsheet.  Enter the formulae, as they would appear when copied to the cell M20 of the same spreadsheet.  (3mks)

7.  Give three advantages of separating data from the applications that use the data in database design. (3mks)

8.  Explain the impact of information on organizations in each of the following areas:  (2mks)

   a) Competition

   b) Pace of growth

9. a) List any four tasks that an electronic spreadsheet should be able to perform other than calculations  (2mks)

    b) Explain what is meant by automatic recalculation as used in a spreadsheet.(1 mk)

10. Describe the functions of the following computer hardware components:

   a)Mouse                     (2 ½  mks)

   b)Scanner.                   (1 ½ mks)

11. a)State two differences between Disk Operating System (DOS) and WINDOWS operating system.

 b. i) Define the term application software  (1mk)

     ii) Give one example of application software (1mk)

12. a)  Give one difference between internal and external commands in Disk Operating System.   (2mks)

      b)  Name two DOS commands that may be used for checking disk errors.  (2mks)

13. Explain how a paragraph can be moved from one place to another in word-processing. 2mks)

14.  Define the term structured programming. (2mks)

SECTION B (60MKS)

Answer question 15 and any other three questions from this section.

15.a)  What is meant by each of the following terms:

 i)   pseudocode        (1 ½ mks)

  ii)  Flowchart           (1 ½ mks)

b) a program is required to list the first 1000 numbers in the series:  2, 4, 6, 8,

10. Draw a flowchart and write a program that can be carried out this task.   (12 mks)

16. The following car details are to be entered in a database; make, date-of-manufacture, colour and cost.

 a) Prepare a suitable database structure showing field names and their field types   (5mks)

 b) Explain how you index the data such that cars of the same make and colours are together   (2mks)

 c)  Write a statement that can be used to select cars of the colour green        (2 mks)

 d) Give an instruction that would;

  i)select cars whose cost lie between 500,000/= and 1,000,000/=  (3 mks)

 ii)Determine the average cost of all cars         (3mks)

17.  a)The diagram below represents the essential features o a computer system. Study the diagram and answer the questions that follow:

i)Name the components (4mks)

            A

            B

            C

            D

ii) On the diagram above, indicate the direction of data flow using arrows.  (3mks)

b) Name the three types of buses in a computer system (3mks)

c) Explain how CPU registers may be used to carry out a basic calculation such as:2 + 7 = 9

d) Name two computers output devices. (1 Mark)

18. a)State three ways in which computer technology may affect employment patterns in organizations   (3mks)

b) State three ways in which computer technology may affect employment patterns in organizations (3mks)

c)Suggest three strategies that can be employed to manage resistance to change  (3mks)

d) Give three advantages of computerization in an organization.  (3mks)

19. a)In a computer based information system, state the purpose of the following files and give one example where such a file may be required in a school.                (8mks)

i) report file

ii)Back-up file

iii)Reference file

iv) Sort file

b) State three precautions that should be taken to ensure that diskettes are well stored.  (3 mks)

c)  Distinguish between “serial” and Indexed sequential” file organization methods.  (2mks)

d)  Distinguish between binary and octal number systems and give an example of each  (2mks)

– multiple choice/yes-no answers
– easy to understand interface e.g. use of icons/drop down menus etc.
– output shown as % probabilities of fault

• to enable logon information to be kept on his computer
• to provide pages customised for Ahmed the next time he logs on
• to implement shopping carts and one-click purchasing
• to be able to distinguish between new and repeat visitors to the website

Twisted pair cables

Coaxial cables

Fibre optic cables

• All nodes ‘listen’ for traffic to sense when the network is idle.
• When a node wishes to transmit, it transmits a ‘request to send’ frame’ (RTS)
• The intended receiving device will transmit a ‘clear to send’ (CTS) frame if it is available.
• All other nodes ‘sense’ the network is busy and wait a random amount of time before trying to transmit

Microwaves can cover shorter distances. On the contrary, radio waves can travel a long distance. Radio wave is usually propagated through sky mode while microwave uses the line of sight propagation. 

• Real time  E.g. turning the wheel must turn the car immediately
• On line - Otherwise system cannot be real time

(a) Like "*kenya*"

• Returns the records of all countries that contain the string "kenya"

(b) Like "*ina"

• Returns records for all countries/regions whose names end in "ina", such as China and Argentina.

(c) Like U*

• Returns records for all countries/regions whose names start with "U", such as UK, USA, and so on.

(d) Not Like U*

• Returns records for all countries/regions whose names start with a character other than "U".

(e) >= "Mexico"

• Returns records of all countries/regions, beginning with Mexico and continuing through the end of the alphabet.

(f) Like "[A-D]*"

• Returns records for countries/regions whose names start with the letters "A" through "D".

(g) "USA" Or "UK"

• Returns records for USA and UK.

https://support.microsoft.com/en-us/office/examples-of-query-criteria-3197228c-8684-4552-ac03-aba746fb29d8

• Font Formatting:

  • Font Style: You can change the font style (e.g., Arial, Times New Roman) for cell content.
  • Font Size: Adjust the size of the text within cells.
  • Bold, Italic, and Underline: Apply these formatting options to emphasize text.
  • Font Color: Change the color of the text.

• Cell Formatting:

  • Number Formats: Apply various number formats, such as currency, percentage, date, and time.
  • Cell Borders: Add or remove borders around cells or cell ranges.
  • Fill Color: Change the background color of cells.
  • Text Alignment: Control how text is aligned within cells (left, right, center, top, bottom).
  • Text Wrapping: Allow text to wrap within a cell if it's too long to fit in one line.

• To provide access to the Internet

• Data Integrity: they provide ways or mechanisms for enforcing data integrity constraints, such as referential integrity. If a record in the parent table is deleted, related records in the child table also get deleted. This ensures accurthe acy and consistency of data stored in the database
• Data Security
• Concurrency control
• Reduces data redundancy
• Data retrieval and querying
• Data indexing
• Data consistency and acid transaction
• Data backup and recovery
• Data sharing and collaboration
• Convenient data maintenance

• A compiled program will only execute on a processor of specific type/family/with same instruction set
• A program run using an interpreter can execute on a computer with any type of processor

Sequence: Sequential execution of a program one line after another

Selection:  Involve the a decision between two or more options e.g  if...then...else

Loops/Repetitions: Used for looping i.e a line of code can be made to execute a given number times before terminating.

• backups/dumps of files
• copy of files on CD/tape streamer
• file generations

(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