1. Availability in the market
2. Initial and maintenance cost
3. User friendliness
4. Compatibility
5. User needs

• she had actually described verification
• data could be incorrect, therefore same incorrect data typed in twice
• accept description of validation process e.g. range check

• 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.

• It ensures that each row has a unique and non-null primary key

• Ease of installation and use
• Application software intended for use in the computer
• Processor type. Some processors do not support all operating systems

• 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

Advantages

• It is intuitive
• Easy to navigate
• Uses menus, pointers and icons thus easy to learn and use
• It lets the user exchange data between different software applications
• The user does not have to learn complicated commands

Disadvantages

• Takes a lot of memory
• A lot of processor power is needed
• Takes up a larger amount of hard disk space than other interfaces
• They need significantly more memory (RAM) to run than other interface types

• Firmware is a software program permanently etched into a hardware device such as a keyboards, hard drive, BIOS, or video cards.
• Device drivers are operating system-specific and hardware-dependent. A device driver acts as a translator between the hardware device and the programs or operating systems that use it. 
• Firmware is a software that controls a system, and firmware's functionality ranges from performing basic tasks like minimal I/O controls to full-fledged software system running with simple or no OS, with scheduler, memory management, etc. 
• A driver, on the other hand, is usually part of the operating system that performs the specific task of controlling a hardware component like a display or USB controller, etc., and gives an interface to use the hardware by Operating system and applications.

method of transmission e.g

• blue tooth
• radio
• optical
• satellite
• infra-red
• microwave

device e.g.

• 3G (WAP) mobile phones/mobile phones/cell phone/remote
• key pad/remote control/keyboard
• infra-red mouse
• multimedia mobile handsets/notebooks
• GPRS (general packet radio service) mobiles
• WLAN(or WiFi) hotspots sited in public areas - e.g. coffee
• shops, railway stations, airports, motorway services
• linked printers
• PDA's (personal digital assistants)
• GPS

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

a) What is an operating system? (1 mark)

• It is a system software that manages the computer hardware. It provides a platform for installation & execution of application software.

b) Briefly explain any four functions of an operating system. (8 marks)
Interrupt handling - When an interrupt occurs, the current state of the CPU is saved & the OS handles the request, after which the OS restores the previous state of the CPU & resumes the interrupted process.
Process scheduling - OS decides which process runs next & for how long.
Memory management - Ensures that each process has enough memory allocated to execute without interfering with other processes.
Error handling - OS provides a mechanism to detect & respond to errors such as segmentation faults, hardware failures, or invalid instructions.

1. Operating system manages the computer hardware thus without it the programs cannot communicate directly to the hardware
2. Provide a user interface through which a user can give instructions to the computer. Without a user interface, it would be difficult to load or run programs
3. other programs depend on the operating system to load them into the memory , allocate resources and schedule processor time, Without operating , there would be nothing to co-ordinate the execution of multiples programs
4. The OS organizes data in files and directories, making it possible for programs to save, retrieve, and modify data.
5. Without it, programs wouldn’t know where or how to store data.
6. The OS controls access to files, memory, and devices, ensuring that one program doesn’t interfere with another.

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. 

One to one  - Each record in the parent table has exactly one related record in the child table, and vice versa.

One to Many -  Each record in the parent table can have multiple related records in the child table, but each record in the child table is related to only one record in the parent table

• star - if one computer goes down the others can still be used
• ring - if one computer goes down the others can not be used

1. MAN
2. WAN
3. PAN
4. LAN

1.State two reasons for the increased use of laptop computers in government offices. [2]

They are small and fit in a small storage space

They are light weight hence can be carried to areas where their services are required

The monitor, system unit, keyboard units are integrated together

Easy to share

Have rechargeable battery

Have low power consumption

2.Computer network technicians prefer to use command-line based operating systems when configuring networks. State three reasons for the preference. [3]

Do not take up a lot of memory

Have direct access to most hardware devices/provide complete control during configuration

Cheaper to acquire as some are freeware/shareware

Faster to execute commands

Difficult to hack/more secure

More stable

3.State three measures that should be put in place in a computer laboratory to safeguard users’ health. [3]

• All power cables must be insulated and hidden from users
• Furniture used must be of standard
• Room should have adequate lighting
• No overcrowding
• Monitor should be fitted with anti glare
• Avoid dust
• Avoid slippery floor
• Avoid bright coloured walls
• Promote use of ergonomic devices

4.State three ways in which barcode readers may be used in schools. [3]

Take inventory of items

Transactions in the school library

Keep track of movement of goods

Track students in and out of school

Used to register roll call

5.State three advantages of flat panel monitors over cathode ray tube monitors as used in computers.                                                                                                                     [3]

• Compact and light/portable/less bulky/occupy less space
• Consume less power
• Low angle distortion
• Improved color depth
• Higher resolution
• Have less radiation
• Produce less heat

6.State three possible reasons for the extinction of daisy wheel printers in the market. [3]

• Slow
• Noisy
• Lack of graphic support
• Monochrome printer
• Supported on font type and size

7.State three ways in which an operating system secures a computer system.             [3]

• User authentication
• Secure user accounts with privileges
• Encryption of data
• Keeping log files
• Auto backup and auto recovery features
• Inbuilt antivirus

8.A law firm prefers to use hard copy output when handling documents for legal matters. State two reasons for this preference.                                                            [2]

• Can be used without electricity
• Can serve as physical evidence/exhibit
• Not easy to change content without leaving evidence
• No need of computer knowledge

9.State the function of each of the following feature in a word processor

a. Thesaurus                                                                                                                    [1]

Feature that suggests words with similar or opposite meanings to the selected word

b. Comments                                                                                                                   [1]

Feature that allows a user to attach remarks

10. With the aid of an example, explain the term multi-level list as used in word processing.                                                                                                                [3]

1. Chapter 10
   1. Summary
      1. xxxxxxxx

Formatting style that shows listed items at different level instead of using one line

11. Distinguish between real-time operating system and distributed operating system. [3]

Accept answers based on data processing concept

12. Explain the function of protect sheet feature in a spreadsheet program.                   [2]

A tool/feature that prevents unwanted changes to the spreadsheet. Requires a user to key in a password inorder to make changes

13. State four computer based careers introduced as a result of computerized data processing method at the airport.                                                                                     [2]

• System analysts
• Web designers
• Network administrators
• Network technicians
• Programmers
• Database Administrators

NB/ Accept any computer based career

14. In a spreadsheet, the formula = If(A1>10,A1*77,A1*50) is entered in a cell. Interpret the results.                                                                                                                        [3]

Checks the value in cell A1if it is more than 10, if the comparison is true then the outcome of the value in cell multiplied by 77 is displayed, else if it is false the results of the value in cell A1 multiplied by 50 are displayed.

15. State a stage in systems development cycle where each of the following activities are carried out:

a. Identifying the technologies that may be used in a proposed system.                       [1]

Accept any sub stage within system analysis e.g. requirement specification, problem definition, information gathering, etc

b. Identifying shortcomings of a system.                                                                       [1]

All stages of system development

c. Preparing the system migration plan.                                                                          [1]

Implementation stage

• Computer viruses
• Unstable power supply
• Hard disk crash
• Theft of data/programs

• data shall only be used for the specific purpose for which it was collected
• data shall be adequate/relevant/not excessive
• data shall be accurate/up to date
• data shall not be kept any longer than necessary
• individuals have the right to see data about them (and have it changed if inaccurate)
• sufficient means taken for security/integrity of data
• data shall not be transferred to a country with lower protection laws
• data users must be registered