Question

why is bio fule was used by human?

Answer 1

Biofuel Uses. When using the work fuel, the tendency is the think of the material in question as a liquid for use in automobiles, trucks, and possibly planes. The truth is, biofuels are looked at as a means of replacing ALL of human energy needs from home heating to vehicle fuel to electricity generation.
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Answer 2

bio fuels have many uses it is used by man for the following uses:
Ethanol and bio diesel are the major bio fuels in production as of 2011. Gasoline engines can use low-level ethanol blends, and modified engines can use higher-level blends. Any unmodified diesel engine can use bio diesel, which can also be mixed in any proportion with regular diesel (see References 1). The U.S. Environmental Protection Agency investigates the impacts of bio fuel use on emissions and the environment.
its to used in
cars and trucks 
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