Advantages

– immediate response to questions/queries
– can see each other watch body language etc.
– easier to have several participants (would be difficult using instant messaging if
several people involved)

Disadvantages

– need for expensive equipment/high set up costs
– sometimes synchronisation problems make it difficult for delegates
– need to train people to use the new technology
– greater use of bandwidth

Modulation refers to the process of converting a digital signal to analog signal at the transmission end while demodulation is to converting analog signal to digital signal at the receiving end

• Bus topology is characterised by common transmission media shared by all the connected nodes
• Star topology is characterised by a central switching node connected directly to each of the multiple nodes in the network

Advantages of Star topology over Bus topology

• Faster communication as compared to bus topology
• Independent line of connection allows freedom of removing or adding nodes

Disadvantages of Star topology over Bus topology

• Expensive as compared to the bus topology
• Long cable length

1. Operating system manages the computer hardware thus without it the programs cannot communicate directly to the hardware
2. Provide a user interface through which a user can give instructions to the computer. Without a user interface, it would be difficult to load or run programs
3. other programs depend on the operating system to load them into the memory , allocate resources and schedule processor time, Without operating , there would be nothing to co-ordinate the execution of multiples programs
4. The OS organizes data in files and directories, making it possible for programs to save, retrieve, and modify data.
5. Without it, programs wouldn’t know where or how to store data.
6. The OS controls access to files, memory, and devices, ensuring that one program doesn’t interfere with another.

Multitasking - the  capability of an operating system to enable users to run two or more programs at once on a single computer

Real time processing - data processing system 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

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

On-line processing - is that type of processing where the result of data processing transaction is available immediately

• data must be up to date
•  data can only be read/used for the purpose for which it was collected
• data must be adequate, relevant and not excessive
• data must be accurate
• data must be destroyed when no longer needed/don’t keep longer than necessary
• data user must register what data stored
• data must be used/collected fairly and lawfully
• data must be held securely
• data must be protected from accidental damage
• only authorised personnel can have access to the data
• fines are imposed for data mis-use
• data should not be passed on to a third party without permission
• a person can view data and have it changed/removed if incorrect

• 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

• Computer viruses
• Unstable power supply
• Hard disk crash
• Theft of data/programs

(a)State what is meant by the terms:

Parallel data transmission

• 8 bits/1 byte/multiple bits sent at a time  
• using many/multiple/8 wires/lines

Serial data transmission

• one bit sent at a time over a single wire

• Use of debugging utilities
• Use of test data
• Dry run / Desk checking

Benefits

• The user is not restricted to the predetermined options//the GUI uses icons and set menus
• The user has more control over the computer settings//in GUI computer settings are protected from the user
• Uses less memory than GUI
• Requires less processing power for the interface
• More processing power is made available for the task

Drawbacks

• The commands used have to be learnt
• The commands used have to be remembered
• The commands used have to be typed in/entered exactly
• Have to remember the exact path/correct name of application
• More prone to errors on data entry Commands have to be typed in//in a GUI can use touchscreens/mice
• Tends to be used by specialist people//GUI is more user-friendly and can be used by non-experts

1. Use a humidifier: Using a humidifier can help maintain a consistent level of humidity in the computer lab, which can prevent the negative effects of low humidity.

2. Avoid dry air: Avoid creating a dry environment in the computer lab by opening windows or using fans to increase air circulation.

3. Regular maintenance: Ensure that all computer components are properly maintained and cleaned to prevent damage due to static electricity.

4. Backup data: Regularly backup all important data to avoid data loss in case of hardware failure caused by low humidity.

5. Monitor humidity levels: Use a hygrometer to monitor the humidity levels in the computer lab and take corrective measures if the levels fall below a safe range.

6. Use anti-static materials: Use anti-static mats or wristbands when handling computer components to prevent static electricity buildup.

(i) Jobs collected together for processing at a later time
(ii) Output produced quickly enough to affect the next input
(iii) User has direct contact with the processor
(iv) User cannot communicate directly with the processor

• used to identify a device
• it is a unique (address)
• it is a static address // it does not change
• it is set by the manufacturer
• the first part is the manufacturer ID/number / identifies the manufacturer
• the second part is the serial number / ID.

• Software may be designed to run on 1 core and not multiple cores
• depends on the task(s)  i.e some tasks cannot be split across cores
• Clock speed also affects speed i.e dual core may have a faster clock speed and quad-core may have slower clock speed so one task may be run faster/slower
• RAM size also affects speed i.e Quad-core may have less RAM  amount of VM being used
• Cache size also affects speed i.e Quad-core may have less cache

Branch of computer science based on enabling computers to
behave like humans/mimic aspects of human intelligence
• AI is implemented in software.
• Combines psychology, biology, linguistics, mathematics, neuroscience,
and philosophy (ethics)
• AI is not the same as the general intelligence of human beings

Uses – Any of the following:
• Game playing (chess, quiz, video games)
• Analytics (analyse buying patterns, predicting behaviours, predictive
text, financial markets)
• Image processing (recognising objects/patterns)
• Logistics (scheduling, order fulfilment)
• Control systems (cars, manufacturing, weapons, navigation)
• Expert systems (medical, mechanical, electrical diagnosis)
• Neural networks (simulating neuron behaviours as in brains)
• Natural languages processing (chatterbots, chatbots, speech
recognition)
• Robotics (dangerous situations, help aged or disabled)

Ethical issues – Any of the following:
• Take the work of humans, thereby affecting employment rates
• Is a computer to be trusted to make decisions (life-death)?

• If a computer discovers something that humans can’t prove, should it be
accepted as truth?
• Do AI machines have rights?
• Will people be comfortable interacting with machines that are
considered intelligent?

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.

• Fetch the instruction – the processor fetches the instruction from a memory address stored in a program counter and transfers the instruction, via a data bus, to an instruction register. At the end of the fetch operation, the counter points to the next instruction that will be read in the next cycle.
• Decode the instruction – the processor decodes the instruction stored in the instruction register, including getting any operands required to complete the instruction.
• Execute the instruction – the decoded instruction is executed.
• Store the result – the result generated by the execute phase is stored in the main memory, and/or sent to an output device. The program counter is updated with feedback from the arithmetic logic unit (ALU), to a different address from which the next instruction will be fetched.

Physical topology - the physical arrangement of nodes of a computer network

Examples

• bus topology
• ring topology
• mesh topology
• star topology

Logical topology- the way data flows in a network

Examples

• Ethernet
• Ring