A Level Computer Science 9618 Paper 13, Oct/Nov 2023

data values that are continuously changing // variable // any value

1 correct line connecting term to description

3 correct lines connecting terms to descriptions

more pixels can be stored / are available

the image is sharper / less pixelated

Working: File size = (2048  1024  16) / (8  1024)

Answer: 4096 kibibytes

Courses must be available to anyone who wishes to follow them

Courses must be available on the internet

Company is willing to share infrastructure with other companies (public)

…which is more economic for the company

There could be a possible loss of control unlike the LAN

…because the data is stored on a remote infrastructure / someone else’s infrastructure // …reliance on external agency to complete tasks, e.g. backups, security

Requires reliable internet connection

…to ensure access to the remote data, more likely with LAN // Increased recurring costs // ...as cloud provider charges must be paid, costs for LAN once only.

Firewall: Monitors incoming and outgoing traffic and rejects any traffic that does not meet the set rules

Encryption: Ensures that if data is intercepted / obtained it cannot be understood without the decryption key

Passwords: Ensures only users with the correct password can access the resources // prevents unauthorised access

Both 1:M relationships correct (TUTOR 1:M COURSE_SCHEDULE and COURSE_INFORMATION 1:M COURSE_SCHEDULE)

SELECT Count(CourseID)

AS NumOfCourses

FROM COURSE_SCHEDULE

WHERE DateStarted > "09/09/23";

The administrator completes a visual check / checks by eye

…that the tutor identifier input matches the tutor identifier on the original document

Double entry check // the administrator (or a second person) enters the number a second time

…and the system compares it with the first entry

First 4 rows of truth table: Y = 1, 1, 0, 1

Last 4 rows of truth table: Y = 0, 0, 0, 0

P AND Q and NOT Q OR R

NOT gate and AND gate and XOR gate

Context-sensitive prompts: As the code is being written

Context-sensitive prompts: …the options to complete the statement are shown

Single stepping: allows the programmer to execute the program one line at a time

Single stepping: …so that the effects of each statement can be seen

To reduce the time it takes to download the program files from the web server // to upload them to the server in the first place

To reduce the amount of storage space used on the web server // user’s device

Disk needs to be prepared for initial use

Disk needs to be checked for errors

A new file system needs to be generated on the disk

The file allocation table needs to be set up

Users are able to trial the program and may offer the programmer constructive feedback

More people might try the program because the trial is free of charge

Allows bugs to be found and corrected on a wide range of computer system configurations improving the programmer’s original program

Users that find the trial useful will buy the program so programmer gets income

Allows the program to be copyrighted and so protects the programmer’s intellectual property rights // no illegal modification allowed

The programmer has ethical guidelines to follow // …so purchasers of programs know the standards being applied // …so programmer does not have to decide what is ethical or not

Clients know programmer is reputable // …recognition of programmer’s skills/knowledge

There may be an entry requirement / exam // … so clients know that the programmer is competent

Professional ethical body provides help and support // Such as legal advice // by appropriate example // Enables programmer to attend the ethical body’s training courses // …to keep skills up to date // to develop skills

Static RAM has faster access time // …because it does not need to be refreshed

…used on the CPU for improvement of CPU cache speed // Static RAM has lower

EEPROM allows frequent / multiple read / write / erase operations

…which means that the contents of the firmware in the headset can be changed easily // …without fully erasing the contents of the firmware in the headset first

The print instructions and data are sent by the laptop to a buffer (at laptop speed)

The data is transferred from the buffer to the printer (at printer speed)

…allowing user to continue using the laptop // and allowing processor to continue processing // …instead of waiting for relatively slower printer

When the buffer is empty an interrupt is sent to the laptop // …requesting more data

naming a correct port (USB / HDMI)

matching justification point 1

matching justification point 2

Validation // a validation method named or described

…protects the data by ensuring that the data is reasonable / sensible and within specified bounds

Difference: Pharming is malicious code that redirects to a fake website. Phishing uses an email to prompt user action. // Pharming is automatic. Phishing requires user action.

Similarity: Both try to obtain financial or personal information // Both are a false representation of an official organisation, e.g. a bank // Both make use of fake websites

Download programs from reputable websites / sources (…as these are less likely to contain malware) // Backup / archive computer systems (…so they can be restored in case of data loss from malware program installation)

Install and run anti-malware program (…so that regular scans can be made for known malware / quarantined / definitions updated)

Using a firewall to block unused ports // Deny administrator privileges to everyday users // Avoid the use of / access to removable devices

Control unit (CU)

Arithmetic and Logic Unit (ALU)

Immediate Access Store (IAS) // (System clock)

Special purpose registers hold the status of a program whereas general purpose registers hold the temporary data while performing operations.

Special purpose registers are specialised for a specific use, whereas general purpose registers are used for any purpose. // General purpose registers can be used by most instructions, whereas special purpose can only be used by certain instruction

PC $\leftarrow$ [PC] + 1

The data in the location pointed to by the MAR is copied to the MDR.

The contents of PC are copied to the MAR.

CIR $\leftarrow$ [MDR]

Division by zero // Runtime error // Out of memory bounds // Program requesting an external device / input // Buffer overflow

D in position 2

A in position 4

B in position 6