Explain the following terms
(a) Disk mirroring
(b) Encryption
(c) Backup
(a) Disk mirroring- Data is written on two or more disks simultaneously.
(b) Encryption - Contents are scrambled so they cannot be understood without a decryption key
(c) Backup - A copy of the data is taken and stored in another location
Give any three advantages of computer networks
What is a web browser?
Describe how the database can be recovered from a system failure
A workshop has a lot of heavy machinery operating throughout the day and requires a cable to connect a workstation to a switch. Which of the following, unshielded twisted pair (UTP) or shielded twisted pair (STP) cable, would be the more suitable? Justify your response.
Shielded twisted pair cable:
A twisted pair cable is made up of four pairs of twisted copper wires, a shielded twisted pair cable applies a shield to each one of the pairs on a cable or to all of the pairs together. This shield can reduce EMI (electromagnetic interference), which would be emitted from heavy machinery. This increased data transmission quality in the workshop. STP can also reduce crosstalk.
Distinguish between Incremental and Full backup
Incremental:
Full:
(ii) The organisation has chosen wireless connectivity over wired connectivity for its new office building. There is no significant difference in the cost of installing either.
Give three reasons why the organisation might prefer wireless connectivity.
May not have space for cables to be installed
Employees and visitors can move around the building without disconnecting
Adding new users just means giving out the SSID and password
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.
Describe one task that is commonly undertaken during the first phase of system development life cycle
KCSE 2003 COMPUTER STUDIES
SECTION A (40 MARKS)
Answer all the questions in this section
1.Computer systems are built from three types of physical components: processors,memories and 1/O devices.
a) State two tasks of a processor (2 mks)
b)State function of 1/O devices (1 mk)
2. Threats to the safety of computer systems take many forms such as: white-collar crime, natural disasters, vandalism and carelessness.Give on way as to how each of these forms of threats can be controlled. 2 mks)
3.a) Explain the term nibbles as used in data representation in computers
b)Perform the following binary arithmetic giving the answers in decimal notation. (3 mks)
i)1110.01111 + 11010001 .011
ii) 1001011.011 - 111.111
4 a) Distinguish between machine and assembly language (2mks)
b) State the type of translator necessary for a program written in: (2mks)
i) High level language
ii)Assembly language
5. Briefly explain the purpose of the following types of program documentation: (3mks)
a) User manual
b) Reference guide
c) Quick reference guide
6. State any two features of a user-friendly program. (2mks)
7 a) Distinguish between labels and formulae with respect to spreadsheets (2mks)
b) Consider the entries in the cells below.
|
Cell |
B2 |
B3 |
C10 |
C11 |
C13 |
|
Entry |
200 |
100 |
B2 |
B3 |
C10 |
State the value displayed in cell C13 (2 mks)
8.List three differences between wide area Networks (WAN) and Local Area Networks (LAN) (3mks)
9. Study the flowchart segment below and state the last value printed from the flowchart. (2 mks)
10. a) What is an expert system (1mk)
b)State any two components of an expert system (2mks)
11. give two reasons why optical disks are better storage media compared to floppy diskettes (2mks)
12.What are the Dos commands used for the following? (2mks)
a) Changing directories
b) Viewing directories
c) Renaming directories
d) Deleting a directory
13. Distinguish between copying and moving text (2mks)
14. a) Name two methods of paper orientation (1mk)
b)Name two keys used to delete text in a document (1 mk)
15.Name two features a Database package (2mks)
SECTION B (60 MKS)
Answer question and any other three questions from this section
16. Study the flowchart below and answer the questions that follow.
a)Write a high-level language program for the above flowchart (7mks)
b)List the outputs of the flowchart above (5 mks)
c) Modify the flowchart so that it adds up all its outputs and displays the sum obtained (3mks)
17. A computer specification has the following details:
a) What is meant by
i) 1.44 MB floppy disk drive?
ii)20 GB hard disk?
iii) 17” SVGA monitor
b) Which operating system might be pre-installed in this computer and why? (2mks)
c) List three multimedia components (3 mks)
d) i) what is meant by computer aided manufacture? (2 mks)
ii) Give two examples of computer aided design software. (2mks)
18. a)Give three examples of network software (3mks)
b)List any three items that may be referred to as data terminal equipment in a network (3 mks)
c)Briefly explain the following terms as used in networking (4mks)
i) Remote communication
ii)Distributed processing
d) State three advantages and two disadvantages of mesh network topology. (5mks)
19. a) a company has decided to computerize their operations. They have decided to purchase package instead of developing their own programs. Give three advantages and two disadvantages of this approach. 5mks)
b) i) explain why a value such as 611233444555 may be displayed as ######### When typed in a cell of a spreadsheet (2mks)
ii) How can the problem in b (i) above be corrected? (2mks)
c) With reasons, briefly describe the most appropriate type of printer output device for the output of: (6mks)
i) Customer invoices on multi-part stationery
ii) Letters to customers
iii)Detailed engineering designs
20. a) Distinguish between the following pair of terms (6mks)
i) Data verification and data validation
ii)Data encryption and passwords
State three categories Operating Systems grouped according to user interface
Give one reason why use of video-conferencing has increased over the last ten years.
– faster communications now widely available
– safety reasons, e.g. increase in terrorist attacks on international flights
– reduced transportation/accommodation/hardware costs
– environmental issues, e.g. reduced carbon footprint
– increase in multinational working
State two reasons for carrying out software updates
Describe the following features of a graphical user interface:
(a) Pointer
(b) Desktop
(a) Pointer
(b) Desktop
List four ways of acquiring software in an organization
Commercial off-the-shelf (COTS) software: Organizations can purchase pre-developed software solutions from commercial vendors. These software products are typically ready-made and designed to fulfill common business needs. Examples include productivity software, customer relationship management (CRM) systems, and accounting software. COTS software can be licensed based on a one-time purchase or a subscription model.
Custom software development: Organizations may choose to develop custom software tailored to their specific requirements. This involves hiring software developers or outsourcing the development work to a third-party vendor. Custom software offers flexibility and can be designed to align with unique business processes and workflows. It allows organizations to have full control over the software's features and functionality.
Open-source software: Open-source software is developed collaboratively and made freely available to the public. Organizations can acquire open-source software without incurring licensing costs. They have the right to use, modify, and distribute the software as per the terms of the open-source license. Open-source software can be an economical option, and it allows organizations to benefit from community-driven development and ongoing improvements.
Software as a Service (SaaS): SaaS refers to software applications that are accessed and used over the internet. Organizations can acquire software on a subscription basis, where the software is hosted and maintained by the vendor. Users access the software through web browsers or dedicated client applications. SaaS eliminates the need for local software installation and offers scalability and accessibility from any location with an internet connection.
Explain how an SSD stores data
Uses transistors( resistors and capacitors) . It can be implemented by the use of NAND or NOR gates. Data is stored on the chip as a charge
Explain how virtual memory can compensate for the limited RAM capacity in a computer.
Mikal has been employed as a computer trainer in an organisation. State three roles that she is likely to play in the organisation
State two benefits of using robots