Computer Studies Paper 1 Questions and Answers - Baringo North Joint Evaluation Mock Exams 2022

Questions

Instructions to Candidates

This paper consists of two sections; A and B.
Answer ALL the questions in section A
Answer question 16 and any other THREE questions from section B
Candidates should answer the questions in English

SECTION A (40 MKS)
Answer all questions in this section.

State the software technological differences between the second generation and the third generation computers [2 marks]
State two ways of ensuring proper ventilation in a computer room [2 marks]
Convert the decimal number 20.375 to it binary number system equivalent [3 marks]
Pat has installed internet in his home computer in order to use it for browsing. State three ways in which he would prevent viruses from infecting the computer. [3 marks]
State three ways of transforming a picture embedded in a Desktop Publishing programme in order to fit in a designated space on a computer. [3 marks]
Distinguish between a line printer and a page printer as used in computers. [2 marks]
Describe virtual reality as used in computers. [2 marks]
State the function of each of the following features of an email software
1. Inbox [1 mark]
2. Draft [1 marks]
1. Explain the term toggle key as used in computer keyboard [2 marks]
2. List two examples of toggle keys on a keyboard [2 marks]
State the type of error that would occur in data processing for each of the following cases:
1. Entering the number 315 instead of 351 [1 marks]
2. Entering the text “Kwys” instead of “Keys” [1 mark]
State four factors to consider when selecting an input device for use in a computer room. [4 marks]
State three functions of Un-Interruptible Power Supply (UPS) [3 marks]
Distinguish between a page break and a column break as used in a word processor. [3 marks]
State three factors to consider when selecting an operating system to install in a computer. [3 marks]
Differentiate between analogue signal and digital signal as used in computers. [2 marks]

SECTION B (60 marks)
Answer ALL questions from this section in the spaces provided.

1. Explain the term dry running as used in program development. [2 marks]
2. Describe three properties of an algorithm. [3 marks]
3. Write an algorithm using both pseudocode and flow chart to print the sum and average of numbers from 1 to n where n is provided by user and n>=1. [10 marks]
1. State four outcomes that may result from using incorrect requirement specifications during system development. [4 marks]
2. A school opted to use direct change over approach when installing a new system. Explain three challenges that the school may face as a result of this approach. [6 marks]
3. State three reasons that may lead an organization to install an intranet. [3 marks]
4. The figure below shows a coaxial cable. State the function of the part labelled A. [2 marks]
Use the figure below to answer the questions that follow:
1. Give the name of the above network topology [1 mark]
2. State three disadvantages of the above topology [3 marks]
3. A publisher intends to use a desktop publishing programme to create a publication which is to have many graphics. State three ways in which the graphics may be acquired for this purpose. [3 marks]
4. Interpret each of the following spreadsheet formula:
  1. =count if (D2:D9,”>” B4) [2 marks]
  2. =sumif (B3:B11,”4M”, D3:D11) [2 marks]
5. 1. The following are the fields of products table in a database created to store records of products manufactured in factory:
    - Product number
    - Product name
    - Price
    - Product description
      State the appropriate data type for each field [4 marks]
1. Explain three features of a graphical user interface as used in computers. [6 marks]
2. State the function of each of the following computer keyboard keys:
  1. Caps Lock [1 mark]
  2. Shift [1 mark]
  3. Home [1 mark]
3. Using two’s complement notation, determine the value of the operation 2510 – 2910. [6 marks]
1. Distinguish between a computer drive and computer driver. [2 marks]
2. State two peripheral devices connected to the computer via PS/2 [1 mark]
3. Jane encountered desktop computer with the following features
  - 3.0 USB ports
  - 4.0 GB primary storage
  - 19” TFT VDU
  - 500 SATA HDD
  - Linux 7.1
    AVG antivirus
    1. Give 3 reasons for wide use of USB gadgets in the society today. [3 marks ]
    2. What is the meaning of the following specifications:
      1. 4.0 GB primary storage [1 mark]
      2. 19” TFT VDU [1 mark]
      3. 500 SATA HDD [1 mark]
      4. Linux 7.1 [1 mark]
    3. Give three factors to consider when selecting an OS to install in your computer. [3 marks]
    4. Describe two symptoms of a computer infected by virus. [2 marks]

Marking Scheme

State the software technological differences between the second generation and the third generation computers [2]
- 2nd generation used assembly languages while 3rd generation used high-level languages
State two ways of ensuring proper ventilation in a computer room [2]
- Wide windows
- Use of vents/ventilators
- Air-conditioners/dehumidifiers/fans
- Providing spacious environment
- Avoid over crowding
Convert the decimal number 20.375 to it binary number system equivalent [3]
- 2010 = 101002
  .375 x 2 = 0.75
  .75 x 2 = 1.5
  .5 x 2 = 1.0
  Hence 20.37510 = 10100.0112
Pat has installed internet in his home computer in order to use it for browsing. State three ways in which he would prevent viruses from infecting the computer. [3]
- Using antivirus software
- Surfing smart e.g. avoid certain sites/ovoid downloading certain attachments
- Use of firewalls to prevent certain attachments/hackers
- Use of complex password to restrict data access
- Scanning downloads
- Enabling the security settings in the browser
State three ways of transforming a picture embedded in a Desktop Publishing programme in order to fit in a designated space on a computer. [3]
- Rotation
- Flipping
- Cropping
- Stretching
- Resizing
Distinguish between a line printer and a page printer as used in computers. [2]
- Line printer prints one line of text at a time while page printer prints a whole page at a time
- Line printer is impact while page printer is non-impact
- Line printer is slow while page printer is fast
- Line printer is noisy while page printer is quiet
Describe virtual reality as used in computers. [2]
- Computer generated simulation of a three-dimensional image/environment that can interarcted with in a seemling real or physical way by a person wear specialized head gear.
State the function of each of the following features of an email software
1. Inbox [1]
  - Storage location where new email messages aare stored.
2. Draft [1]
  - A storage location where messages composed but not yet sent are stored
1. Explain the term toggle key as used in computer keyboard [2]
  - Keys that alternate the input mode. When press ON they intended to perform a task, when pressed OFF, they perform a different task.
2. List two examples of toggle keys on a keyboard [2]
  - Caps lock, Insert, Num lock and Scroll locl
State the type of error that would occur in data processing for each of the following cases:
1. Entering the number 315 instead of 351 [1]
  - Transposition error
2. Entering the text “Kwys” instead of “Keys” [1]
  - Transcription error
State four factors to consider when selecting an input device for use in a computer room. [4]
- Compatibility with existing system
- Cost of the device
- Extra features in the device
- Purpose of the device
- Nature of data to be captured
- Portability
State three functions of Un-Interruptible Power Supply (UPS) [3]
- Stabilizes power
- Stores power
- Alerts user through an alarme system when poer is down
Distinguish between a page break and a column break as used in a word processor. [3]
- Page breaks marks the end of a page while column page marks the end of a column
  NB. Accept illustrations
State three factors to consider when selecting an operating system to install in a computer. [3]
- Hardware configuration a computer e.. RAM.HDD, and othersystemrequirements
- Type of computer in terms of size and make
- User-friendliness
- Number of users it can support
- Cost
- Applications intended for use in the computer
Differentiate between analogue signal and digital signal as used in computers. [2]
- Analog data uses values that change continuously while digital uses values that are descrett
  NB. Accept illustrations
1. Explain the term dry running as used in program development. [2]
  - Process where a programmer manually (pen & Pencil) work through a code to trace the values of variables and to identify errors
2. Describe three properties of an algorithm. [3]
  - Must have a start and a stop
  - Steps must be precise
  - Statements must not have more than one meaning/no ambiguity
  - There should be clear indentation of statements
  - Input,Output and Procesing statements should be clearly defined using keywords
3. Write an algorithm using both pseudocode and flow chart to print the sum and average of numbers from 1 to n where n is provided by user and n>=1. [10]
1. State four outcomes that may result from using incorrect requirement specifications during system development. [4]
  - System may end up being costly
  - System may be delivered late
  - System may not meet user specification
  - Higher cost of maintenance
  - System may be unreliable and prone to errors
  - System may not meet legal requirements
2. A school opted to use direct change over approach when installing a new system. Explain three challenges that the school may face as a result of this approach. [6]
  - In case of a problem thre will be no fall back
  - There will be less time for users to familirise themselves with new system
  - Possibility of sabotage by users because of less time to monitor and manage stress resistance
3. State three reasons that may lead an organization to install an intranet. [3]
  - to isolate resource from the internet
  - to provide communation and collaboration amongst organization staff
  - to publish and share valuable information easily with users
  - to safely run critical applications
4. The figure below shows a coaxial cable. State the function of the part labelled A. [2]
  - Used to provide insulation
  - To block electromagnetic fields from interference
  - To protect signal distortion
Use the figure below to answer the questions that follow:.
1. Give the name of the above network topology [1]
  - Bus
2. State three disadvantages of the above topology [3]
  - Slow
  - T-Joints weaken the signal (BNC connectors)
  - A bus that is not terminated causes Ringing
3. A publisher intends to use a desktop publishing programme to create a publication which is to have many graphics. State three ways in which the graphics may be acquired for this purpose. [3]
  - Using digital camera
  - Scanning thegraphics from other sources
  - Downloading from the Internet
  - Drawing/Drawing tools
  - Clipart
4. Interpret each of the following spreadsheet formula:
  1. =count if(D2:D9,”>”B4) [2]
    - Count those values in the range D2;D9 with values greater than the value in cell B4
  2. =sumif(B3:B11,”4M”,D3:D11) [2]
    - Sum the values in the cell range D3;D11 for records whose corresponding values in cell range B3:B11 equals to “4M”
5. 1. The following are the fields of products table in a database created to store records of products manufactured in factory:
    - Product number Autonumber/Text
    - Product name Text/String
    - Price Currency/Number
    - Product description Memo/Text/String
      State the appropriate data type for each field [4]
1. Explain three features of a graphical user interface as used in computers. [6]
  - Windows
  - Icons
  - Menus
  - Pointers
2. State the function of each of the following computer keyboard keys:
  1. Caps Lock [1]
    - Is a toggle key when ON the characters typed are in uppercase and when OFF the characters typed are in lower case
  2. Shift [1]
    - Used together with alphanumeric key to type the alternate character
  3. Home [1]
    - Used to take the cursor to the beginning of a line
    - Used in conjunction with other keys to modify the function of the key
3. Using two’s complement notation, determine the value of the operation 2510 – 2910. [6]
  - 2510 = 0001 10012
  - 2910 = 0001 11012
    
    2s complement of 2910 = 1110 0010 + 1 = 1110 0011
  - Adding the two binary numbers
    0001 1001 + 1110 0011 = 11111100
1. Distinguish between a computer drive and computer driver. [2]
  - A computer drive is a hardware component that facilitates storage and retrieval of data on incorporated to the operating system the controls the functionality of their specific peripheral devices. A removable storage device while a computer driver is sets of instructions installed
    Difference @ 2 Marks
2. State two peripheral devices connected to the computer via PS2 [1 ]
  - Keyboard
  - Mouse
3. Jane encountered desktop computer with the following features
  - 3.0 USB ports
  - 4.0 GB primary storage
  - 19” TFT VDU
  - 500 SATA HDD
  - Linux 7.1
  - AVG antivirus
    1. Give 3 reasons for wide use of USB gadgets in the society today. [3]
      - Allows multiple peripheral devices on a single port
      - Quality data transmission
      - Faster data transmission
    2. What is the meaning of the following specifications :
      - 4.0 GB primary storage [1 ]
      -19” TFT VDU [1]
      - 500 SATA HDD [1]
      -Linux 7.1 [1]
    3. Give three factors to consider when selecting an OS to install in your computer. [3]
      - Processor speed
      - Purpose of the computer
      - Memory size
      - Compatibility and
      - Upgradeablility
      - User needs
      - User friendliness
      - Make of the computer
    4. Describe two symptoms of a computer infected by virus. (2]
      - Hang ups
      - Shutting down frequently
      - Error messages
      - Quizical messages
      - file increase and decrease