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:

• Microwave (oven) (1)
• Washing machine (1)
• Dishwasher (1)
• Digital camera (1)
• Satellite navigation/satnav system (1)
• Traffic light(s) (1)
• Central heating controller/thermostat (1)
• Digital watch/fitness tracker (1)
• Vending machine (1)
• Car (as it contains embedded systems) (1)

Allow any other device that contains an embedded system.

Do not accept general purpose devices such as a laptop, desktop computer, tablet or smartphone (these can run many different programs).

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

• The compiler translates the whole program/complete source code in one go (1) whereas the interpreter translates one line/statement at a time (1)
• The compiler translates all of the source code before any of it is run/executed (1) but the interpreter translates each line/statement as it reads it (1)
• The interpreter translates one line/statement at a time (1) and the compiler translates the whole program/source code together (1)

Accept the compiler point and the interpreter point in either order.

Do not accept responses about object code/executable files, when the translated code is executed, how errors are reported, or speed/memory use.

Do not accept 'the interpreter executes/runs each line' on its own, without saying that it translates one line/statement at a time.

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

• Splits the data/file into packets (1) so each packet can be sent separately across the network (1)
• Adds a packet/sequence number to each packet (1) so the packets can be put back into the correct order at the destination (1)
• Detects lost/missing packets (1) so they can be requested/resent (1)
• Creates a connection between the two computers/hosts (1) before the file is sent (1)

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

Allow 'segments' for 'packets' (TCP divides the data into segments, which become packets at the internet layer).

Do not accept 'sends the data/file' on its own without saying what the transport layer does to the data.

Do not accept naming TCP or a port number on its own without expansion.

Do not accept routing/addressing packets using IP addresses, which is the internet layer.