Coal is used to produce electricity by burning in coal-fire power stations, and solid refined coal is easy to transport and can be used in coal-burning equipment. Given these facts, solid materials used to produce electricity by burning in what need to be transported firs among the following options:
- Conifers
 - animals
 - it needs them
 - humans
 - heat energy
 - important habitats
 - power stations
 - batteries


 

       power stations  