Which of the following fuels has the highest calorific value ?
(a) natural gas
(b) liquefied petroleum gas
(c) coal gas
(d) hydrogen gas
The calorific value of a fuel is 40000 kJ/kg. This fuel is most likely to be :
(a) biogas
(b) methane
(c) hydrogen gas
(d) liquefied petroleum gas
Which of the following is not a fossil fuel?(a) coal(b) petroleum gas(c) biogas(d) natural gas