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

1. SECTION A
2.  Answer all questions in this section
3. What is a computer?                                                                                                            1mks
4. State three physical components that make up a computer                                                 3mks
5. State the hardware technological differences between the second generation and third generation computers                                                                                                          2mks
6. State and explain three characteristics of a computer                                                         3mks
7. State the functions of the following special memories in a computer                                3mks
8. Buffers
9.  
10. Registers
11. Cache
12.  
13. Define the following as used in data representation in a computer                                  (5mks)
14. Bit
15.  
16.  
17. Byte
18.  
19.  
20. Nibble
21.  
22.  
23.  
24. Word
25.  
26.  
27.  
28. Word-length
29.  
30.  
31. State two reasons why a DVD is superior to a typical compact disk                               (2mks)
32. State three advantages of flat panel monitors over cathode ray tube monitors                   3mks
33. Explain the following terms as used in word processing                                                  3mks
34. Section breaks
35. Thesaurus
36. Superscript
37. State two advantages of  impact printers                                                                             2mks
38. State the function of the following keys on the computer keyboard                                  3mks
39. Enter key
40. Insert key
41. Delete key
42. State the technology used by the following secondary devices to store data                      3mks
43. Magnetic storage devices
44. Solid state storage devices
45. Optical storage devices
46. State three reasons why an operating system is important in a computer                         3mks
47. A typical computer’s main memory consists of both volatile and non-volatile memory.
48. i)  Explain what is meant by the term volatile memory                                          (1mark)
49. ii) What is normally stored in the non-volatile part of a computer’s main memory (1mark)
50. Explain why having cache memory can improve the performance of the CPU         (2mks)
51. What is a computer system?                                                                                           (1mk
52. Give two differences between a solid state drive (SSD) and a hard disk drive (HDD)   2mks
53. State three categories of software classified according User license agreement              (3mks)
54. State two disadvantages of Random Access Memory                                                       (1mk)
55.  
56.  
57. a) Explain the functions performed by the following components of a processor   (2 marks)
58. Control unit

Word wrap - Is a word processing feature in which a word that does not fit in the current line is automatically moved at the start of the next line

Justification - refers to aligning text on both left and right margins

Drop cap - Make the first character of a paragraph occupy more than one line below it

• In a client-server network, every device is either a client or a server whereas in a peer-to-peer network each computer has equal responsibility and each has the ability to work as both a server and a client

• The different factors that can influence the performance of a network include: bandwidth, network design, data collisions, and excess broadcast traffic.
• The bandwidth can influence through the method of transmission and medium used

Virus

• - program/software that replicates/copies itself
• – can delete or alter files/data stored on a computer
•  – can make the computer “crash”/run slow

Pharming -

• malicious code/software installed on a user’s hard drive/actual webserver
•  – this code redirects user to a fake website (without their knowledge)
•  – to obtain personal/financial information/data

Phishing

• - legitimate-looking emails sent to a user
• – as soon as the recipient opens/clicks on the link in the email/attachment …
• – … the user is directed to a fake website (without their knowledge)
• – To obtain personal/financial information/data

Interviews

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.

• an use Internet connection and telephone at the same time
• much faster data transfer speed
• always “on”
• charged for number of bytes/flat rate per month rather than actual time on line
• more bandwidth

Router

input

• from sensors
• from camera images [Max 2]

processing

• analyse data from sensors
• calculate average traffic flow/speed
• send signals to adjust change lights/timing

output

• change lights at the junction
• change timing plan

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

TV remote, wireless mouse , wireless keyboard, used by robots to gauge distance and avoid obstacles,

• Unfamiliar graphics or quizzical messages appear on the screen
• Programs taking longer than usual to load
• Less memory allowance than usual
• Unusual error messages occurring more frequently

• Extra bit on each data-byte that
•  Does not transmit data
• Makes the number of ones in a byte always even or always odd
• Error in the transmission of a bit will make the even/odd wrong
• The problem of two errors in one byte not being found
• Parity block

highest = -1
for student = 1 to 3000
total = 0
for exam = 1 to 8
input mark
total = total + mark
if mark > highest then highest = mark
next
average = total/8
output average
next
output highest

Python code:

highest = -1
for student in range(1, 3001):
    total = 0
    for exam in range(1, 9):
        mark = int(input("Enter mark: "))
        total += mark
        if mark > highest:
            highest = mark
    average = total / 8
    print("Average:", average)
print("Highest mark:", highest)

VBA Code

Option Explicit

Sub CalculateAverageAndHighest()
    Dim highest As Integer
    Dim total As Integer
    Dim mark As Integer
    Dim average As Double
    
    highest = -1
    
    For student = 1 To 3000
        total = 0
        For exam = 1 To 8
            mark = InputBox("Enter mark:")
            total = total + mark
            If mark > highest Then
                highest = mark
            End If
        Next exam
        average = total / 8
        MsgBox "Average: " & average
    Next student
    
    MsgBox "Highest mark: " & highest
End Sub

• A physical file contains the original data whereas a logical file does not contain any data
• A physical file contains one record format while a logical file can contain up to 32 record formats
• A physical file can exist without a logical file while a logical file cannot exist without a physical file

Blackout: This is unexpected discontinuation of power supply in the laboratory.

Power sag: Sudden drop of voltage levels that lasts less than a second.

Transients/ surge: High voltage flowing.

Brownout: Partial blackout where there's low voltage flow.

SECTION A (40 MARKS)

1.What is meant by

    a)Analogue data

     b)Digital data                           (4 mks)

2. Distinguish between transcription and transposition types of errors and give an example of each  (4mks)

3. a)What are peripheral devices?  (1mk)

   b)Give two examples of peripheral devices  (1mk)

4a)What meant by the term user-friendly as used in software development? (1mk)

  b)Distinguish between the terms single-tasking and multi-user as used in operating systems  (2mks)

5.What actions should be taken in case of a fire outbreak in the computer laboratory?  (4mks)

6a) What is an Internet Service Provider?    (1mk)

  b) An employee in a business company is charged with the responsibility of putting the company advertisements on the Internet.

 i) State the professional title of the employee. (1mk)

ii) Give an example of software used by this employee to carry out the above task.    (1mk)

7.Differentiate between COM ports and LPT ports     (2mks)

8.Explain two ways in which ICT can enhance commerce.  (2mks)

9. Explain the following software terms:

    a) Portability       (1 mk)

    b) Modularity      (1 mk)

10. a) State two application areas of desktop publishing software. (2mks)

     b) Explain the following graphic terms:                                                                                     

     i) Rotate (1 mk)

    ii) Crop  (1mk)

12. a)List two arithmetic operations that can be performed on a row of numeric data in a word processing table.    (1 mk)

     b) In each case of (a) above, write the expression used.  (2mks)

13. List two methods of gathering information during the system development process   (2mks)

14.Name three types of optical disks.(3mks)

15.The diagram below shows a formatted plate surface of a storage disk.

            Shade and label:

            a)         one sector                                                                                ( 1mk)

            b)         One block                                                                                (1mk)

SECTION B (60 MKS)

Answer question 16 and any other three questions from this section in the  space provided

16 a) List two examples of:

       i) Third generation languages    (2mks)

       ii) Object oriented languages    (2 mks)

b) Draw a flowchart to compare three non-equal numeric values A, B, C and prints the largest of the three. (11 mks)

17 a) One of the functions of an operating system is job scheduling.  Explain what is meant by job scheduling.   (1mk)

    b)List and explain three types of user interfaces.                      (6 mks)

    c)Describe the following categories of software:

       i) Firmware                 (1mk)

       ii) Proprietary software  (1mk)

     d) a new company XYZ intends to go into the business of desktop publishing. Advise the company on three computer hardware system specification features to consider as a measure of enhancing performance. (6 mks)

18. a) distinguish between the following sets of terms as used in spreadsheets.        (2mks)

     i)Worksheet and workbook

     ii) Filtering and sorting

     b) State one way in which a user may reverse the last action taken in a spreadsheet package.        (1 mk)

     c)The following is a sample of a payroll. The worksheet row and column headings are marked  1, 2, 3, .  and A, B, C.  respectively