What is the electric potential of the neutral wire in a mains supply cable ?

Along with live wire and neutral wire, a third wire is also used in domestic electric wiring. What name is given to this third wire?

List the colours of the three wires in the cable connected to the plug of an electric iron.

If fuses of 250 m A, 500 mA, 1 A, 5 A and 10 A were available, which one would be the most suitable for protecting an amplifier rated at 240 V, 180 W?

When does an electric short circuit occur?