Edexcel GCSE Computer Science (1CP2) Exam Questions

• C 128 (1)
• The only correct answer is C. The correct answer is 128.
• A is not correct because 6 bits give only 64 different combinations
• B is not correct because 127 is the largest 7-bit value, not the number of characters that 7 bits can represent
• D is not correct because 256 characters need 8 bits, as used by 8-bit extended ASCII

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

• Program instructions are stored in main memory/RAM (1)
• The data used by the program is stored in main memory/RAM (1)
• The CPU fetches/reads instructions from main memory to execute them (1)
• The program can be run without the instructions being input again (1)

Allow 'the program is stored in memory' for one mark.

Do not accept answers about programs being stored on secondary storage, such as a hard disk or USB memory stick.

Do not accept answers that only describe the von Neumann architecture (e.g. having a CPU and memory) without stating that instructions are stored in main memory.

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 up to two marks for a linked explanation such as:

• Data is encrypted/scrambled (1) so it cannot be read/understood if it is intercepted (1)
• The customer's bank/personal details are kept secure/private (1) because the data is encrypted/scrambled during transmission (1)
• The customer's login details/password cannot be read by an eavesdropper (1) because HTTPS encrypts/scrambles the data sent to and from the web server (1)

For both marks, the expansion must follow/associate with the statement.

Allow 'scrambled' as an alternative to 'encrypted'.

Do not accept 'it is more secure/safe' or 'the data is secure' on its own, without saying how it is made secure (e.g. encryption/scrambling).

Do not accept faster loading/speed, or claims that HTTPS stops viruses or always proves the website is genuine.

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

• 0100 (1)
• 0000 (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.