Daily Practice - GCSE Computer Science

Evaluate X = NOT A AND B when A = 0 and B = 1.

An 8-bit register stores the value 01100000 (denary 96). State the resulting 8-bit binary value after a left shift by 1 place, and state whether an overflow occurs.

An uncompressed file is 6000 KB. After lossless compression it is 1500 KB. Calculate the compression ratio in the form n:1 (original size : compressed size).

Give one specific way this code could be refined without changing what it does: a = 5, b = 3, c = a + b, PRINT c

A table called staff has fields staffId, name, department and salary, storing these records: staffId | name | department | salary, 1 | Ben | Sales | 24000, 2 | Chloe | IT | 31000, 3 | Dan | Sales | 27000. State which staffId(s) would be returned by: SELECT staffId FROM staff WHERE department = 'Sales' AND salary > 25000;