Interfaces enable computer users to interact with the operating system. State three advantages of using a graphical user interface (GUI) for loading programs and files.
List three electronic data processing modes used in computers
Sarah uses a range of computing devices to complete her studies, including a desktop computer at home, a laptop at school and her mobile phone. Outline two advantages of cloud computing for Sarah.
Cloud computing refers to the delivery of on-demand computing resources over the internet. Instead of relying on a local server or personal computer, cloud computing allows users to access and utilize a wide range of computing services and resources hosted on remote servers.
List two types of network software
Computer Studies Paper 1 2021 KCSE Prediction Section B Qs. 17,18 and 19
17. a) i) Explain the term search as used in the Internet. [2]
A web based application that locates items or information from the World Wide Web
ii) Peter intends to download a movie from the Internet. State the three factors that may determine the total time taken to complete the download. [3]
b) Wakulima online is an organization that runs a web based system for assisting farmers to obtain market for their produce. State four technological reasons that may cause a farmer not to access the organization’s system. [4]
c) Explain a situation when each of the following Desktop Publishing program features may be used when creating a publication:
i. Cropping [2]
Applies to graphics – used to trim/remove/hide some portions in the graphics
ii. Transparency [2]
Used to make background of a graphic to be clear/visible
d. List two areas where infrared waves are used in data communication. [2]
18. a) List four activities of the planning stage of systems development. Ignore this question, marks redistributed elsewhere
b) Explain a circumstance when each of the following feasibility studies are carried out during systems development.
i. Technical [3]
Done to determine whether technology exists to support the proposed solution
ii. Economic [3]
Done to determine whether the proposed solution is economically viable
iii. Schedule [3]
Done to determine whether the proposed system can be done within an acceptable time.
c) Table 1 and Table 2 are related tables in a database. Use them to answer the questions that follow.
Table 1
|
Dept Code |
Dept Name |
|
001 |
Computer |
|
002 |
Aviation |
|
003 |
Engineering |
Table 2
|
DeptID |
Student Registration No. |
Student’s Name |
|
002 |
St01 |
Alex Too |
|
003 |
St02 |
Naomi Komi |
|
002 |
St03 |
Peter Kengo |
i. Identify the appropriate primary key for each table. [2]
Table 1 – Dept code, Student Registration No
ii. Explain two benefits of enforcing referential integrity in the database. [4]
19. a) Describe each of the following validation checks as used in data processing.
i. Preserve check [2]
Ignore this question, marks redistributed elsewhere
ii. Data type check [2]
Ensure correct type of data is entered for the field
iii. Check digit [2]
This is a number added/calculated by the computer to a binary number. The check digit ensures correct transmission of the binary number.
b. Write each of the following abbreviations in full:
i) BCD [1½]
Binary Coded Decimal
ii) EBCD [
This question was thrown out and marks redistributed elsewhere
iii) ASCII [1½]
American Standard Code for Information Interchange
c) Using 10-bits binary number system, perform the following decimal operation using two’s complement. [6]
12910 - 12810
+129 = 00 1000 0001
128 = 00 1000 0000
-128 = 11 0111 1111 (ones complement)
+1
11 1000 0000 (Twos complement)
129- 128
00 1000 0001
+ 11 1000 0000
100 0000 0001
Hence = 00 0000 00012 or 12 (the overflow bit is ignored)
State the types of storage devices used in a computer
Primary Storage (Memory):
Secondary Storage (Mass Storage):
Identify three ways in which this new technology has affected employees. In each case, explain why it has had an impact.
Identify four different types of computer network.
Describe and give an example of one syntax and one logical programming error.
Syntax
• An error that occurs when a command does not follow the expected syntax of the language, e.g. when a keyword is incorrectly spelt
• Incorrect: IF A ADN B Then
• Correct: IF A AND B Then
Logical
• An error that causes a program to output an incorrect answer (that does not necessarily crash the program)
• An algorithm that calculates a person’s age from their date of birth, but ends up giving negative numbers
Describe one way developers ensure that their software addresses inclusivity issues.
Incorporate language support features in their software, which allows users to select their preferred language. This can be achieved through multi-language user interfaces and providing translation capabilities. By doing so, developers address language barriers and make the software accessible to a broader audience, demonstrating a commitment to cultural inclusivity.
Gender inclusivity – use gender-neutral language in examples
Cultural/Racial inclusivity – use a variety of ethnicities in photos
Ability inclusivity – represent awareness of disability in some examples
Sexual preference inclusivity – use language that is supportive of LGBTQI+ people
Explain the Fetch – Execute cycle and provide an example of a Central Processing Unit (CPU) component for each stage of the cycle
The Fetch – Execute cycle is a sequence of actions, performed by the processor as it fetches
a program instruction from its memory, determines what the instruction wants to do and
carries out those actions. The stages of the cycle are provided below.
Many organisations provide free public access to a wireless network.
Explain three ethical, legal or data privacy issues that an organisation should be aware of when allowing this access
Explain why a software developer should be responsible for addressing ergonomic issues in software design.
Responsibilities of the software developer is to ensure that the ergonomics focuses on making software user-friendly, reduces repetitive motions or eyestrain and enables movements of users to promote comfort and efficiency.
Software can be designed with adjustable text sizes and screen brightness settings to prevent eye strain, offering users a way to customise their visual experience for better comfort during prolonged use.
Computer Studies Paper 1 2021 KCSE Prediction Section B Qs. 17,18 and 19
17. a) i) Explain the term search as used in the Internet. [2]
A web based application that locates items or information from the World Wide Web
ii) Peter intends to download a movie from the Internet. State the three factors that may determine the total time taken to complete the download. [3]
b) Wakulima online is an organization that runs a web based system for assisting farmers to obtain market for their produce. State four technological reasons that may cause a farmer not to access the organization’s system. [4]
c) Explain a situation when each of the following Desktop Publishing program features may be used when creating a publication:
i. Cropping [2]
Applies to graphics – used to trim/remove/hide some portions in the graphics
ii. Transparency [2]
Used to make background of a graphic to be clear/visible
d. List two areas where infrared waves are used in data communication. [2]
18. a) List four activities of the planning stage of systems development. Ignore this question, marks redistributed elsewhere
b) Explain a circumstance when each of the following feasibility studies are carried out during systems development.
i. Technical [3]
Done to determine whether technology exists to support the proposed solution
ii. Economic [3]
Done to determine whether the proposed solution is economically viable
iii. Schedule [3]
Done to determine whether the proposed system can be done within an acceptable time.
c) Table 1 and Table 2 are related tables in a database. Use them to answer the questions that follow.
Table 1
|
Dept Code |
Dept Name |
|
001 |
Computer |
|
002 |
Aviation |
|
003 |
Engineering |
Table 2
|
DeptID |
Student Registration No. |
Student’s Name |
|
002 |
St01 |
Alex Too |
|
003 |
St02 |
Naomi Komi |
|
002 |
St03 |
Peter Kengo |
i. Identify the appropriate primary key for each table. [2]
Table 1 – Dept code, Student Registration No
ii. Explain two benefits of enforcing referential integrity in the database. [4]
19. a) Describe each of the following validation checks as used in data processing.
i. Preserve check [2]
Ignore this question, marks redistributed elsewhere
ii. Data type check [2]
Ensure correct type of data is entered for the field
iii. Check digit [2]
This is a number added/calculated by the computer to a binary number. The check digit ensures correct transmission of the binary number.
b. Write each of the following abbreviations in full:
i) BCD [1½]
Binary Coded Decimal
ii) EBCD [
This question was thrown out and marks redistributed elsewhere
iii) ASCII [1½]
American Standard Code for Information Interchange
c) Using 10-bits binary number system, perform the following decimal operation using two’s complement. [6]
12910 - 12810
+129 = 00 1000 0001
128 = 00 1000 0000
-128 = 11 0111 1111 (ones complement)
+1
11 1000 0000 (Twos complement)
129- 128
00 1000 0001
+ 11 1000 0000
100 0000 0001
Hence = 00 0000 00012 or 12 (the overflow bit is ignored)
Give one example of wireless technology
method of transmission e.g
device e.g.
Students are using their wireless notebooks to complete their work in a classroom. They will need to connect wirelessly to a printer to print their answers at the end of the lesson.
Describe how CSMA/CA (Carrier-sense multiple access with collision avoidance) operates in the above scenario.
Give two reasons why hexadecimal is often used instead of binary in computer
science.
What is a referential integrity constraint?
Give two benefits for the supermarket manager of using point of sale (POS) terminals.
Explain why a developer, who is good at both low-level and high-level programming, would normally use high-level languages when writing programs [4 marks]