Renewable source of energy is —

1. coal
2. fossil fuels
3. natural gas
4. sun

A natural source providing us energy continuously is called -

1. non-renewable
2. conventional
3. renewable
4. none of the above

The energy obtained from the sun is called -

1. solar
2. renewable
3. non-renewable
4. both (a) and (b)

The value of solar constant is

1. 1.34 kW km^-2
2. 1.34 kW m^-2
3. 1.34 kW m²
4. none of the above