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 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 description such as:

• Instructions can manipulate/control the hardware/memory/registers directly (1) so the driver can control the specific device it is written for (1)
• The code is written for one specific processor/architecture (1) so it works with the exact hardware it will control (1)
• The programmer controls exactly how memory/registers are used (1) so the code is efficient and needs little memory, which suits a device that has limited memory (1)
• Each instruction maps to one machine code instruction (1) so the driver code is small enough to fit in the memory of the device (1)

Extra detail, such as naming the device the driver controls, is not needed to earn the marks.

Do not accept 'it is closer to machine code' on its own: it must be developed to show how this helps the driver, e.g. it can control the hardware directly.

Do not accept 'it is faster/quicker' with no link to the hardware/device, e.g. the device responds quickly.

Do not accept 'it is easier to learn', 'it is easier to debug' or 'it takes less time to write'.

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

• If one cable/device fails, the other devices on the network are not affected (1) because each device has its own separate connection to the central switch (1)
• Faults are easier to find (1) because each device has its own cable, so the faulty cable can be checked on its own (1)
• Data is sent only to the intended device (1) because the central switch forwards the data only to the device it is addressed to (1)
• Data transfer is fast (1) because each device has its own cable, so devices do not share the cable with each other (1)
• New devices can be added easily (1) because a device only needs one cable to a spare port on the central switch (1)

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

A benefit stated on its own can earn one mark; the second mark is only for a linked reason.

Accept 'switch' for the central device.

Do not accept 'server' or 'hub' for the central device.

Do not accept 'hub', as a hub sends data to all devices, not only to the intended device.

Do not award a mark for responses that say only that the network is better/more reliable/easier without naming a benefit.