The electric power is generated at 11 kV because :

1. voltage higher than 11 kV causes insulation difficulties
2. voltage lower than 11 kV involves a very high current
3. it reduces the loss of energy in the form of heat
4. both (1) and (2)

The power generated at the generating station is transmitted to the main sub station at voltage :

1. 33 kV
2. 11 kV
3. 132 kV
4. none of these

The neutral and the earth wires are connected at the local sub station so that :

1. the potential increases
2. the neutral and earth wires are at the same potential
3. the potential of neutral wire increases
4. none of the above

The main switch is a:

1. single pole switch
2. triple pole switch
3. double pole switch
4. can be any of these