Daily Practice - GCSE Computer Science

A logic circuit has inputs C and D. C feeds into a NOT gate; the output of the NOT gate and D feed into an OR gate, giving output Y. Write the Boolean expression for Y and state its value when C = 1 and D = 0.

Convert the denary number 5 to a 4-bit binary number.

State one example of a file format that commonly uses lossy compression.

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;