• memory used up/slows down computer/alters setting/systems failure
• erases files/erases data/corrupts data/data needs restoring
• infects other computers on the network
• production loss/financial loss

– if one station/cable fails, others are not affected
– easier to identify faults when using star topologies
– it is easier to expand this type of network
– performance doesn’t deteriorate under load

• College authorities are the experts in the problem
• A system Analyst is an expert with computers
• The two need to pool resources to come up with a clear definition
• Agree on the outcomes so that when the system is , there are a set of criteria to judge it by

• 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

• Main memory is transitory/temporary/volatile, secondary storage is (semi-)permanent
• The processor can only use data/instructions that are in the main memory
• Main memory is directly accessible to the processor, secondary storage is not directly accessible to the processor 

Definition

• Disk formatting is the process of preparing a data storage media for initial use

Reasons:

• To make a disk blank for reuse
• To make it compatible with another operating system
• to create tracks and sectors for first time use

• A software which can display a webpage on a user's computer screen

• Knowledge base – is the systems’ database of knowledge about a particular subject. It contains relevant facts, beliefs, assumptions and procedures for solving a particular problem
• Inference engine – this is the software that controls the search for knowledge in the knowledge base and produces conclusions. It takes the problem posed by the user and seeks to analyze it in order to arrive at a conclusion.
• User interface- this is the display screen that enables the user interact with the system.

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)

Enrolment:
- Data input on line
- Individual records validated
- Speed mismatch implications
- Indexes updated immediately
Exam grades:
- Data input twice
- Off line
- Run as a batch
- At otherwise downtime

• VM is used when RAM is full  i.e part of the secondary storage used as (temporary) RAM/VM
• Data from RAM is moved to the secondary storage/VM (to make space in RAM)
• RAM can then be filled with new data
• When data in VM is needed it is moved back to RAM

• Optical scanner is used read data by use a beam of light while a magnetic ink scanner is used to read data encoded/written using magnetic ink by magnetising the ink characters and translating them

• Phased means that only one part of the system is implemented at a time

1. Enable resource sharing
2. Facilitate remote communication
3. Enable distributed processing
4. Provide better data security and management

It has a header

• that contains the destination address
• that contains the packet number
• that contains the originator’s address

It has a payload

It has a trailer.

device: beeper/loud speaker
use: to indicate barcode correctly read/error in reading barcode
device: (LCD) screen/monitor
use: to show prices and other information about goods
device: touch screen
use: to show prices and other information about goods/to select items that need to be
weighed/identified
device: weighing machine
use: to find weight of loose items (e.g. fruit) to enable pricing
device: (magnetic) card reader/CHIP and PIN reader
use: to read customer’s debit/credit card/enable customer to pay for goods using a
credit or debit card
device: printer
use: to print receipts

• Broadcast Radio
• Infrared
• Bluetooth
• Microwaves
• Satellite

• a repeater is a two-port device that amplifies a signal from one port to another
• a switch is a multiport device that uses a table of addresses to send a signal through the correct port

Manages memory (RAM)

•  Allocates memory to programs currently executing 

Ensures programs/data do not corrupt each other

• Ensures all programs and data including itself is stored in correct memory locations

Manages processes

• Ensures different processes can utilise the CPU and do not interfere with each other or crash  

Allows the user to run programs 

• On a multitasking operating system, it ensures that all tasks appear to run simultaneously 

Other roles

• Allocates time slices
• Scheduling of programs
• Handles interrupts
• Allows the user to configure hardware

• used to identify a device
• it is a unique (address)
• it is a static address // it does not change
• it is set by the manufacturer
• the first part is the manufacturer ID/number / identifies the manufacturer
• the second part is the serial number / ID.