• can cover large areas
• requires minimal land-based transmission support
• requires minimal infrastructure to provide internet access
• minimal impact on the environment or humans.

Disadvantages

• transmission speeds are not comparable with other forms of transmission
• data costs are expensive by comparison to other forms of transmission
• expensive to deliver.

• 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

• Commands have to be typed in full with no mistakes
• Requires memorization of commands
• Uses less memory

GUI

• Due to graphics, GUI uses a lot of memory
• GUI is more user friendly
• Cannot operate properly if memory is low

Comparison

• Both carry out file management
• Both are operating systems
• Both control software and hardware

• Information that a website stores about a user on their hard disk; this enables
  the website to remember details about the user when they next visit the website.

(b) Spyware

• Program installed on a PC to gather information about the user. It monitors
  every key press and relays the information back to the home base

(c) Phishing

• Sending an email that claims to be from a legitimate company; the recipient is then directed to a bogus website where their personal details will be collected

(d)Spam

• Junk/ (unsolicited) electronic mail advertising products and services sent to a general mailing list.

(e) Pharming

• Malicious code installed on a PC or on a server. This code directs users to a
  a fraudulent website without their knowledge.

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)

Advantages

• can gather specific information and additional information
• high response rate to questions
• The question can be rephrased to seek more clarification
• it is possible to win the confidence of the interviewee and get honest answers

Disadvantages

• time consuming
• responses to interview questions are subjective.
• the interviewee may not open up on some sensitive issues
•  

Questionnaire

Advantages

• easy to administer
• can be anonymous.

Disadvantages

• fixed (inflexible) design
• potential differences in understanding and interpretation.

Cache memory
A processor’s cache is a small portion of incredibly fast memory. It has read and write speeds far higher than hard disk drives and even SSDs. The cache is used to store frequently used information and reduces time wasted in fetching the same information from main memory time and time again

Clock speed
A processor’s clock speed relates to the frequency of the pulses generated by the system clock. The higher the frequency, the more cycles of the fetch-execute cycle can be completed in the same period of time.

Word length
A word is a group of bits that is treated as a single unit by a processor. Words can be used for representing both instructions and data. The length of a word is the number of bits that are assigned to it, with higher word lengths allowing for more bits to be transferred and manipulated as a single unit.

Address bus width
The width of a bus relates to the number wires that make up the bus. Increasing the width of the address bus increases the range of addresses that it can specify, hence increasing the computer’s amount of addressable memory. Adding a single wire doubles the number of addressable memory locations

Data bus width
Increasing the width of the data bus increases the volume of data that can be transferred over the bus at any one time. A wider data bus allows the processor to fetch more data from the main memory in one cycle of the fetch-execute cycle, reducing the number of cycles required to fetch large volumes of data.

(b) One disadvantage of using the Unicode character set, instead of the ASCII character set, is

that the text stored takes up more storage space

• Each character is encoded using more bits