• High-level languages have built-in functions;
• High-level languages have built-in libraries;
•  High-level languages have more support/help;
• High-level languages have structures (such as selection and iteration);
• High-level languages can be less machine-dependent/more portable;
• It (usually) requires fewer lines of code to be written;
• It is (usually) quicker to develop code in high-level languages;
• It is easier to find mistakes in code;
• The code is easier to maintain//understand;
• • It is easier to structure code in high-level languages;

• This approach causes minimum disruption

There could be several possible causes for the issues Jane is experiencing with her computer keyboard, including:

1. Software Issues
   - Cause: Outdated or corrupt system files, drivers, or operating system.
   - Solution:
     - Ensure the operating system and drivers are up-to-date.
     - Run a system file checker to repair any corrupted system files (e.g., on Windows, run "sfc /scannow" from the Command Prompt).
     - Consider reinstalling the operating system if issues persist.

2. Hardware Issues:
   - Cause: Physical damage or malfunction in the keyboard hardware.
   - Solution:
     - Check for physical damage or debris under the keys and clean the keyboard if necessary.
     - If cleaning doesn't help, consider replacing the keyboard with a new one.

3. Resource Overload:
   - Cause: The computer may be running too many background processes or lacking sufficient hardware resources.
   - Solution:
     - Close unnecessary background applications and processes to free up system resources.
     - Consider upgrading the computer's RAM, CPU, or storage if it's outdated and unable to handle current software demands.
     - Use task manager or activity monitor to identify and terminate resource-intensive processes.

4. Malware or Viruses:
   - Cause: Malicious software can slow down a computer, cause hanging, and delay startup.
   - Solution:
     - Perform a full system scan using reputable antivirus or anti-malware software to remove any threats.
     - Ensure that the operating system's security patches are up-to-date.

5. Disk Fragmentation:
   - Cause: Fragmented files can slow down the loading of applications and overall system performance.
   - Solution:
     - Run a disk defragmentation tool (e.g., Windows' built-in tool) to optimize file storage on the hard drive.
     - Consider upgrading to a solid-state drive (SSD) for faster application loading times.

6. Insufficient Storage:
   - Cause: If the hard drive is nearly full, it can cause slow performance.
   - Solution:
     - Free up space by deleting unnecessary files and programs.
     - Consider upgrading to a larger capacity hard drive or SSD if storage space remains an issue.

7. Background Processes and Startup Items:
   - Cause: Too many unnecessary programs running in the background or starting up with the computer.
   - Solution:
     - Disable or remove unnecessary startup items and background processes to improve startup time.
     - Use the Task Manager or System Preferences (on macOS) to manage startup items.

It's important to diagnose the specific cause of the issues Jane is facing by troubleshooting each potential problem one by one. In some cases, a combination of these solutions may be necessary to fully resolve the problems with her computer keyboard.

Any one of:
• To allow connected machines to communicate
• To provide the rules of communication between two networked devices

(a) \(F C_{16}\)

(b) \(8 A_{16}\)

(c) \(93_{10}\)

• a repeater is a two-port device that amplifies a signal from one port to another
• a switch is a multiport device that uses a table of addresses to send a signal through the correct port

Both translate source code written in high level programming languages into machine code.
Compiler: Produces a single executable file that is portable between machines
Interpreter: Source code needs a special environment to run
Compiler: Needs to be compiled for a particular architecture
Interpreter: Can run on any architecture that has the translator/interpreter
Complier: Entire source code file is translated at once
Interpreter: Code is translated line by line
Compiler: Provides error report at the end of the compilation
Interpreter: Errors more obvious in the sequence
Compiler: The program source code is not available (so helps protect IP)
Interpreter: Source code is available
Compiler: Only has to be translated once (affecting the speed of execution)
Interpreter: Has to be translated each time, therefore (affecting the speed of execution)
Compiler: Requires two files to be maintained (one for execution and for editing purposes)
Interpreter: Requires only one file to be maintained
 

• backups/dumps of files
• copy of files on CD/tape streamer
• file generations

Advantages

• no wires
• fast/high-speed wireless Internet access
• WLAN is faster than a modem or mobile
• WLAN for working at home one day a week/teleworkers
• see internet content away on the move
• create and send multimedia messages to mobiles or e-mail
• picture messaging - send photos/pictures text/sound/recorded
• greetings from mobiles to mobiles/PCs
• instant transmission - no busy signals/no searching for phone jacks
• download e-mail and file attachments on mobile
• watch live webcast on mobile/hotspot
• listen to streaming video on mobile/hotspot
• news/weather/sport/games while on the move
• access information from mobile anytime
• send/receive/delete e-mail while on the move
• wireless Inbox on mobile - to contacts and calendar
• view business appointments while out of the office on mobile
• send corporate e-mail while out of the office - even behind a firewall on mobile
• wireless internet connection from chat rooms for discussions with colleagues while on the move
• give visual demonstrations from mobile and colleagues watch back at the office

 disadvantages e.g.

• WLAN speeds are slower than Net access at work/narrow band width
• any one within the WLAN nodes range with an appropriate device can use your WLAN and broad band link
• any one who walks past your house or WLAN linked into a corporate system can access sensitive information or credit card details
• 3G phones not compatible with 2G phones
• Blue tooth - has limited range
• blocked signal/distorted signal/weak signal/lag
• health problems from microwaves

• File handling - Copy/move/delete
• Anti-virus software - To protect files from attack by a virus
• Defragmentation - To keep files sensibly arranged on the hard drive
• Format - To divide the surface of a drive into smaller areas to aid storage

• Windows for example a word processing application and a spreadsheet

• Menus, for example, allow the user to perform operations or run applications such as right-click to create a new folder  

• Icons for example a picture of linked computers for networking

• Pointers(mouse or touchscreen)  for example to select items/trigger events  

• Shortcuts for example to frequently used applications for example having a shortcut to your mail client on your desktop

• File navigation for example when searching the hard disc for a file/folder using a browser

• copying / deleting / moving/sorting/naming/searching of files or folders for example copying of a file from the hard drive to a USB pen drive (File handling)

• Desktop customisation for example changing the colours and background image

• Copy and paste for example between applications e.g. copying a graph from a spreadsheet to a word processor

• Error messages for example provide users with error/warning/help messages for example ‘printer out of paper’ 

• A laser printer makes use of powdered ink and static electricity to print
• Unlike inkjet printers which print line-by-line, laser printers print the whole page in one go

Steps

• The data from the  file to be printed is sent to a printer driver
• The printer driver checks that the data is in an understandable format
• The printer driver checks if the printer is able to carry out the print job
• The data is sent to the printer and is stored in a printer buffer
• A printing drum in the printer is given a positve charge. A laser beam removes the positive charge in some areas. This leaves negatively charged areas which matches the characters/images to be printed
•  

Direct Change-Over

• A date is chosen for the shutdown of the old system, then at that time, the old system
  is turned off and the new system is implemented

Phased

• Parts of the new system are implemented in stages or for a period of time, both the old and the new system are running together until all parts of the system are implemented.

RAID (Redundant Array of Independent Disks) technology refers to a method of combining multiple physical disk drives into a logical unit to improve performance, data availability, and data redundancy. RAID technology is commonly used in storage systems to provide fault tolerance, data protection, and increased storage performance.

The primary purpose of RAID is to create a more reliable and robust storage solution by spreading data across multiple drives and implementing various data redundancy techniques. This helps to mitigate the risk of data loss and system downtime in case of drive failures.

There are different levels or configurations of RAID, each offering different features and trade-offs. The most commonly used RAID levels are:

1. RAID 0 (Striping): Data is split evenly across multiple drives, resulting in increased performance as data can be accessed from multiple drives simultaneously. However, there is no redundancy, so if one drive fails, data loss can occur.

2. RAID 1 (Mirroring): Data is duplicated or mirrored across two drives, providing redundancy. If one drive fails, the other drive can still function and serve the data. RAID 1 offers data protection but does not offer increased performance.

3. RAID 5 (Striping with Parity): Data and parity information are striped across multiple drives, providing both increased performance and fault tolerance. Parity information allows for the recovery of data in case of a single drive failure. RAID 5 requires a minimum of three drives.

4. RAID 10 (Combination of Mirroring and Striping): RAID 10 combines elements of RAID 1 and RAID 0. It involves mirroring data across two sets of drives and then striping the mirrored sets for increased performance and fault tolerance. RAID 10 provides high levels of data redundancy and performance but requires a minimum of four drives.

• user changes his mind
• new government legalisation/company policy company changes
• changes in hardware
• changes in software/upgrades/new versions
• improved operating efficiency/ease of use

b) What Simeon and Anna said about the life of Jesus during the dedication. (7mks)

Jesus would save people

He would bring glory to Israel

He would be a light to the gentiles

He would be a universal savoir

He would bring judgment to the Israelites

Many people would oppose his work

He would reveal secret thoughts of people

He would be the source of redemption for Jerusalem

Explain the purpose of each of the following features of a spreadsheet chart (KCSE 2021, Q19 (a))

Legend

• Legends are a small visual representation of the chart's data series to understand each without confusion.

A data series

• is a row or column of numbers that are entered in a worksheet and plotted in your chart, such as a list of quarterly business profits
• A group of related data points or markers that are plotted in charts and graphs

Data Marker

• A symbol on the chart that represents a single value in the worksheet.
• A column, dot, pie slice, or another symbol in the chart representing a data value

https://www.lifewire.com/data-series-data-points-data-labels-3123411

Router

• It is a utility software that places file data in adjacent sectors to free up space for more data and reduce access time for files stored

Multi-tasking - It is a data processing modes where a single CPU processing more than one task or program apparently at the same time

Time-sharing - a processing mode where a single CPU processes tasks from more than one user apparently at the same time

Time-sharing - this is a processing mode in which the CPU serves two or more users with different processing requirements ( tasks)

On-line processing - is a mode of processing where the result of data processing transaction is available immediately

Real-time processing - is a mode of data processing in which the time interval required to process and respond to inputs is so small that the response itself is useful for controlling the physical activity of a process