Edexcel GCSE Computer Science (1CP2) Exam Questions

• B 4 (1)
• The only correct answer is B. The correct answer is 4 (2 bits give 2^2 = 4 values).
• A is not correct because 2 is the number of bits used to store each sample
• C is not correct because 8 different amplitude values would need 3 bits
• D is not correct because 16 different amplitude values would need 4 bits

Award one mark for:

• Laser (1)

Allow laser beam

Do not accept read/write head

Do not accept pits

Do not accept lands

Do not accept reflective surface

Do not accept magnet/magnetic

Award one mark for any of the following up to a maximum of two marks:

• A binary digit (1)
• Has the value 0 or 1 (1)
• The smallest unit of data storage (1)
• A single 0 or 1 (1)

Allow binary digit/binary place value for binary digit

Allow a single binary digit for a single 0 or 1

Do not accept a group of 8 bits/half a nibble of 4 bits, which describe a byte or a nibble

Do not accept a binary number/binary on its own

Award up to two marks for a linked description such as:

• Parts of a file are moved so they are stored together/in consecutive locations (1) so the read/write head has less distance to travel to read the file (1)
• Files are rearranged so that each file is stored in one block (1) which reduces the time taken to open/load the file (1)
• Free space on the disk is collected into one area (1) so new files can be saved without becoming fragmented (1)
• The parts of each fragmented file are put in order (1) so fewer movements of the read/write head are needed to read it (1)

Do not accept responses about compressing files, deleting files or increasing the amount of storage, as these are not what defragmentation software does.

Do not accept 'it makes the disk faster' without saying how the files are changed.

Award one mark for each correct nibble in the correct order:

• 1110 (1)
• 0100 (1)

0 marks if the response is not 8-bit binary.

Indicative content

File management

• The operating system organises the practice's patient records into folders, so staff can find a patient's record quickly during an appointment.
• It carries out file operations such as saving, moving, renaming and deleting, so a dentist can save updated notes to the correct record.
• It sets permissions on shared folders and files, so that only authorised staff, such as dentists, can open a patient's clinical records; this reduces the risk of confidential records being seen by the wrong staff.
• It can give read-only access to some files, so receptionists can view appointment details but cannot change clinical notes.
• It shows the size of files and the free space on the practice's shared storage, so managers can see when more storage is needed for records.

User management

• The operating system creates a user account for each member of staff, with a username and password, so that each person has their own access to the system.
• It allocates access rights to each account, so receptionists, dentists and managers each see only the folders and files their role needs.
• It allows accounts to be grouped by role, so a new dentist can be given the same permissions as the existing dentists quickly instead of setting each one by hand.
• It can require strong passwords, which makes it harder for one member of staff to log on using another person's account and open patient records.
• It can disable or delete an account when a member of staff leaves, so that they can no longer open patient records.

Levels

• Level 0 (0 marks): No rewardable content.
• Level 1 (1–2 marks): Basic, independent points are made, showing elements of understanding of key concepts/principles of computer science. (AO1) The discussion will contain basic information with little linkage between points made or application to the context. (AO2)
• Level 2 (3–4 marks): Demonstrates adequate understanding of key concepts/principles of computer science. (AO1) The discussion shows some linkages and lines of reasoning with some structure and application to the context. (AO2)
• Level 3 (5–6 marks): Demonstrates comprehensive understanding of key concepts/principles of computer science to support the discussion being presented. (AO1) The discussion is well developed, with sustained lines of reasoning that are coherent and logically structured, and which clearly apply to the context. (AO2)

Level 3 responses must cover both file management and user management and develop how each supports the practice, for example linking permissions to who can open patient records. Answers that only state basic, undeveloped points such as 'the operating system puts files in folders' or 'users have a username and password', with little reference to the practice, are limited to Level 1 (maximum 2 marks).

Do not accept backup, disk defragmentation or anti-malware software as operating system file management, or encryption, as these are outside the operating system's file management; they are utility software or security measures.

Indicative content

Ease of learning, use and debug

• High-level language statements are written in English-like words and mathematical symbols, so the students can read the quiz game code and understand what each line does.
• The language is easier to learn than a low-level language, so students who are new to programming can start writing the quiz game quickly.
• Errors are easier to find and fix because the code is readable; for example, the students can check a line that updates a score against the rule they intended.
• The students do not need to know how the processor carries out each statement, so they can concentrate on the quiz questions and rules.

Data structures

• High-level languages provide lists or arrays, so the names and scores of all the players can be stored under one name and processed with a loop.
• A record can store a player's name and score as one item; in some languages a dictionary or class can be used instead, which keeps related data together.
• Using a data structure makes the code shorter and easier to understand than separate variables for every player's name and score.

Built-in functions and library routines

• High-level languages provide built-in functions such as print and input, so the students can display a question and read a player's answer without writing the underlying code.
• Library routines such as a random number generator can be used to choose quiz questions, saving the students time.
• String-handling routines can check or compare a player's answer, so the students do not have to write these routines themselves.
• Reusing tested routines reduces the amount of code the students write and can reduce errors in the quiz game.

Levels

• Level 0 (0 marks): No rewardable content.
• Level 1 (1–2 marks): Basic, independent points are made, showing elements of understanding of key concepts/principles of computer science. (AO1) The discussion will contain basic information with little linkage between points made or application to the context. (AO2)
• Level 2 (3–4 marks): Demonstrates adequate understanding of key concepts/principles of computer science. (AO1) The discussion shows some linkages and lines of reasoning with some structure and application to the context. (AO2)
• Level 3 (5–6 marks): Demonstrates comprehensive understanding of key concepts/principles of computer science to support the discussion being presented. (AO1) The discussion is well developed, with sustained lines of reasoning that are coherent and logically structured, and which clearly apply to the context. (AO2)

Additional guidance: Credit only points applied to the quiz game and the students; comparison with low-level languages is not required, but a correct contrast may support a point if it is applied. Do not award generic claims such as 'high-level programs run faster', 'work on any computer' or 'students do not need to learn syntax' unless they are justified for the quiz game.

Level 3 responses must cover all three bullet areas with linked reasoning that explains why the characteristic helps the students finish the game quickly with few errors; an answer covering only two bullet areas is limited to Level 2. Do not award the idea that high-level code is already machine code or is understood directly by the processor. Accept dictionaries or classes as equivalents of records.