What is the most important characteristic of a good fuel?

What are hot spots inside the Earth's crust?

The energy liberated by burning $1 \,g$ of charcoal is approximately: (in $,kJ$)

Give two uses of coke.

The major problem in harnessing nuclear energy is how to

"Electricity generated by the water stored in a dam can be considered to be another form of solar energy." Explain by describing the series of energy transformations in sequence taking place during the process.