Probably firewood, since it is readily available.
Carbohydrates
Our body's first source of energy is carbohydrates. When we eat carbohydrates, our body breaks them down into glucose, which is used as fuel to power our cells and organs.
The main fuel source for the work of the cell is the mitochondria.
The main fuel source for the work of the cell is the mitochondria.
The main fuel source for the work of the cell is the mitochondria.
No. It can be an energy source, but it's not a fuel.
Fuel, heat, oxygen...obviously.
Coal is a type of rock that can be burned as a fuel source to generate heat and electricity.
Burnt Wood to cook and heat their houses.
A source of heat, a source of fuel, and oxygen.
No
Yes, ethanol releases carbon dioxide when it is used as a fuel source.