alternative energy question three

 question three~  what are biofuels~

~ https://www.greenfacts.org/en/biofuels/l-2/1-definition.htm

~ biofuels are made from waste of living plants and animals
ex: wood, crops , corn , fishery produces food industry by produces.
primary biofuels wood burned for heating , cooking , secondary biofuels are from processing biomass into ethanal which can be used in gasoline.  ~