Detailed Answer

(a)

• More applications can run because there is more available memory
• Larger application can run with less RAM;

(b)

• Applications run slower
• Reduced amount of hard drive space available for use

Detailed Answer

(a)

• Managing memory
• Managing peripherals
• Processor management
• Scheduling

(b)

• A dedicated operating system for a mobile phone takes up less storage space than a full-sized operating system, allowing the device to function more quickly.
• It doesn’t contain unnecessary features, making it more efficient.
• A dedicated OS can be customized to suit the specific hardware of the mobile phone, avoiding compatibility issues associated with generic OS that support multiple types of hardware.

(c)

• The desired temperature is set by the user.
• Sensors detect temperature and continuously send readings to the microprocessor.
• The microprocessor compares the actual temperature with the desired one.
• If the temperature is too hot or cold, the microprocessor sends a signal to the actuator to adjust the temperature.

Detailed Answer

• An interrupt is a signal sent to the CPU by hardware or software.
• The function of an interrupt is to alert the CPU to suspend the execution of the current program.
• Upon receiving the interrupt, control is transferred to the interrupt handler, which saves the state of the current program to the interrupt stack, services the interrupt, and then resumes normal CPU activity.

Detailed Answer

(a)

• Virtual Memory: Allows the hard drive to act as primary memory when necessary, enabling the computer to extend its memory beyond physical RAM.
• Paging: A technique where data is divided into small blocks (pages) that are transferred between the main memory and secondary storage, making efficient use of memory space.
• Multitasking: Enables the CPU to run multiple applications at once, giving the illusion that the applications are running simultaneously.
• Scheduling: The operating system allocates CPU time to different processes based on priority, ensuring that all tasks get executed efficiently.
• Policies: Define how resources should be allocated and which activities should be performed, ensuring fair and efficient resource usage.
• Interrupt Handling: Allows the system to immediately execute urgent tasks by suspending less important tasks, ensuring that critical processes are addressed without delay.

(b)

• Virtual Machine: The operating system presents a virtual machine to the user, hiding the complexities of the underlying hardware.
• Virtualization of Devices: The operating system uses virtual representations for physical devices (e.g., using drive letters for hard drives), making it easier for users to interact with hardware without needing to understand its structure.
• Use of Icons: Peripheral devices and storage drives are represented by icons, abstracting the underlying hardware from the user.

(c)

• The memory in a laptop is generally smaller than that in a file server, as laptops are designed for personal use with less storage and fewer programs running simultaneously.
• A file server, being designed for multiple users and tasks, has larger memory to handle more extensive data storage and retrieval processes.

(d)

• Light Sensor
• Infra-red/Motion Sensor

(e)

• The sensors continuously send data to the processor, converting analog data to digital.
• The processor compares the sensor data with pre-set threshold values to determine if the light level is low and if there are people present.
• If both conditions are met, the processor sends a signal to the actuator to turn on the lights.

(f)

• A timer is set for let's say 5 minutes after detecting the room has been unoccupied.
• If the light level is still below the pre-set value, the lights will stay on during this time, even if no further movement is detected.
• After 5 minutes, the lights will switch off if no further presence is detected.

Detailed Answer

• The operating system makes maximum use of the available (limited) memory, providing the essential features needed for the phone.
• It avoids wasting memory space with unwanted or inappropriate features, ensuring that only necessary functionality is included.
• It ensures a higher level of security by limiting access to sensitive system resources and by managing permissions effectively.
• The operating system makes efficient use of the phone's hardware equipment, ensuring that resources are allocated effectively for better performance.

Detailed Answer

• Scheduling
• Policies
• Multitasking
• Virtual Memory
• Paging
• Interrupt
• Polling

Detailed Answer

(a)

        

            maxPopulation = 0
            cityWithMaxPopulation = ""

            FOR i FROM 0 TO 99
                IF Population[i] > maxPopulation THEN
                    maxPopulation = Population[i]
                    cityWithMaxPopulation = Cities[i]
                ENDIF
            ENDFOR

            OUTPUT cityWithMaxPopulation
        
    

(b)

        
            highEmissionCities = []

            FOR i FROM 0 TO 99
                perCapitaEmission = CO2Emissions[i] / Population[i]
                IF perCapitaEmission > 1000 THEN
                    APPEND Cities[i] TO highEmissionCities
                ENDIF
            ENDFOR

            OUTPUT highEmissionCities
        
    

(c)

        
            totalFines = 0

            FOR i FROM 0 TO 99
                perCapitaEmission = CO2Emissions[i] / Population[i]

                IF perCapitaEmission > 999 AND perCapitaEmission < 2000 THEN
                    fine = 100 * Population[i]
                ELSE IF perCapitaEmission > 1999 AND perCapitaEmission < 3000 THEN
                    fine = 125 * Population[i]
                ELSE IF perCapitaEmission > 2999 THEN
                    fine = 150 * Population[i]
                ENDIF

                totalFines = totalFines + fine

            ENDFOR

            OUTPUT totalFines
        
    

Detailed Answer

• func(5) = func(4) + func(3)
• func(4) = func(3) + func(2)
• func(3) = func(2) + func(1)
• func(2) = func(1) + func(0) = 1 + 0

So:

• func(3) = 1 + 1 = 2
• func(4) = 2 + 1 = 3
• func(5) = 3 + 2 = 5

Detailed Answer

• Input: 4 — Divisible by 2 but not by 5, so not outputted.
• Input: 7 — Not divisible by 2, so not outputted.
• Input: 10 — Divisible by 2 and 5, so outputted.
• Input: 13 — Not divisible by 2, so not outputted.
• Input: 15 — Divisible by 2 but not by 5, so outputted.
• Input: 18 — Divisible by 2 but not by 5, so not outputted.
• Input: 20 — Divisible by 2 and 5, so outputted.
• Input: 25 — Not divisible by 2, so not outputted.

Output: 10, 20

Detailed Answer

• Pre-processing
• Parsing
• Semantic analysis
• Syntax analysis
• Optimisation
• Linking

Detailed Answer

Detailed Answer

(a)

        
            INPUT playerName, pointsScored
            FOR i FROM 0 TO 14
                IF NAMES[i] == playerName THEN
                    SCORES[i] = SCORES[i] + pointsScored
                ENDIF
            ENDFOR
        
    

(b)

        
            FOR i FROM 0 TO 14
                IF POSITIONS[i] == "Guard" AND SCORES[i] > 100 THEN
                    OUTPUT NAMES[i] + " - " + POSITIONS[i]
                ENDIF
            ENDFOR