admin@kcseforecast.com

Q&A-KCSE Computer Studies Paper 1

Compare and contrast CLI and GUI

CLI

  • 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
Question Image

Describe two features you would expect to see in the expert system’s interactive user interface.

– multiple choice/yes-no answers
– easy to understand interface e.g. use of icons/drop down menus etc.
– output shown as % probabilities of fault

Question Image

Describe two benefits of using USB connections between a computer and a device.

  • devices are automatically detected and configured when initially attached
  • Impossible to connect device incorrectly/connector only fits one way
  • has become the industry standard
  • supports multiple data transmission speeds
  • lots of support base for USB software developers
  • supported by many operating systems
  • backward compatible
  • faster transmission compared to wireless
Question Image

State three ways of transforming a picture embedded in a DTP program in order to fit on a designated space on a document (kcse 2019 paper 1)

  • Resizing using resize handles
  • Rotating
  • Cropping
  • Flipping
  • Moving
Question Image

Differentiate between object code and source code

  • Object code refers to a program in machine language while source code to a program in a high level language that must be translated to object code for it to be machine readable
Question Image

List two primary functions of a domain name server.

  •  map IP addresses to names and criteria
  • To map directory services
  • Maintain directory of domain names
  • To map URL (web address) to IP address
Question Image

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.

  • All nodes ‘listen’ for traffic to sense when the network is idle.
  • When a node wishes to transmit, it transmits a ‘request to send’ frame’ (RTS)
  • The intended receiving device will transmit a ‘clear to send’ (CTS) frame if it is available.
  • All other nodes ‘sense’ the network is busy and wait a random amount of time before trying to transmit
Question Image

Explain each of the strategies listed below.

(a) Phishing

(b) DoS

 

(a) Phishing

  • Phishing is a strategy that encourages a computer user to part with sensitive information such as bank details hence the term ‘phishing’ – i.e. fishing – trying to catch someone out. For example, a perpetrator sends a user an email that appears to be genuine, for example, pretending to be a bank or a lawyer requesting that the user verify bank account details or send money to assist in the completing of a legal case.

(b) DoS

  • DoS is a means of attack on a specific user/system/website which involves overloading a target with too much network traffic resulting in system slowdown, shutdown or a violation of security.
Question Image

KCSE 2021 Computer Studies Paper Prediction 1                SECTION B

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

16. a) With the aid of a flow chart, describe a loop control structure as used in programming. [4]  

A control structure that allows statement(s) to be repeatedly executed until a certain condition is met                                                                                                      2mks

NB. Accept any other looping construct

Question Image

State advantages and disadvantages of Solid State Drives and Hard Disk Drives

Advantages of  of Hard Disk Drive

  • Hard disk drives are cheaper per gigabyte than solid state drives.
  • Hard disks have a longer lifespan than solid state drives

Disadvantages of Hard Disk Drives

  • Consumes more power than SDD
  • They are noisy.
  • They are slower than solid state drives.
  • They are susceptible to wear and tear as they have movable parts.

Advantages of Solid State Drives

  • Are faster than HDDs
  • It is more durable as it does not have moving parts
  • Consumes less power
  • Are not noisy

Disadvantages of SDD

  • It costs more than a conventional hard disk
  • Have fewer write/erase cycles compared to a hard disk drive
  • Lost data cannot not be recovered
Question Image

Your friend wishes to install a wireless network in his office. Explain to him the difference between guided and unguided media

  • Guided media uses cables to connect to computers whereas unguided media uses waves.
Question Image

Describe an environmental issue related to the disposal of computer components

Many components that go into computer systems are toxic and dangerous to the environment if released or disposed of inappropriately.
Heavy metals are used in batteries and circuits and these can pollute groundwater or kill animals if left exposed on landfill. Large quantities of plastics are used in systems, which take a long time to break down, some of the plastic will eventually break down into toxins as it degrades.

Question Image

Explain why solid state storage is the best choice for a fitness tracker.

  • Because it will be subject to movement  and it does not use mechanical/moving parts

          OR

  • Solid state storage is smaller/more compact so better suited for a wearable device

          OR

  • Doesn’t have moving parts  because they could be disrupted during use
Question Image

The introduction of a new system involves evaluation and maintenance once the system is
implemented.
Describe the evaluation and maintenance stage of the systems development life cycle (SDLC)
and provide one example of an activity undertaken in this stage.

  • Continually monitoring, evaluating and updating the system once it is operational. Activities include rectifying bugs, requesting changes, updating aspects, finding errors, maintaining code etc.
Question Image

State the seven layers of the OSI model

  1. Application
  2. Presentation
  3. Session
  4. Transport
  5. Network
  6. Data link
  7. Physical

Distinguish between a file and a folder

A file is a collection of related data given a unique name while a folder is named storage location on a storage media that contains related files

Question Image

Describe one effect of not having primary keys in tables in a relational database

Without a primary key, a table in a database may have duplicate rows, making data not uniquely identifiable. This can lead to issues with data integrity and challenges in maintaining relationships between tables. Retrieving and updating specific records becomes problematic, and setting referential integrity constraints is impossible, potentially leading to loss of data.

Question Image

Explain why the organization's management and the analyst need to work together to define the problem accurately during system development

  • College authorities are the experts in the problem
  • A system Analyst is an expert with computers
  • The two need to pool resources to come up with a clear definition
  • Agree on the outcomes so that when the system is , there are a set of criteria to judge it by
Question Image

Give one difference between a compiled program and interpreted program

  • A compiled program will only execute on a processor of specific type/family/with same instruction set
  • A program run using an interpreter can execute on a computer with any type of processor;
Question Image

Explain two ways in which an interpreter and a compiler are different.

  • They execute code differently – a compiler reads a complete program at once, an interpreter reads a program line-by-line
  • they identify errors in different ways – a compiler does not allow a program to run until error-free, an interpreter runs the program until the first error.
Question Image