Respuesta :
Answer: Option A) Some of the energy is lost as heat
Explanation:
Energy conversion is not always 100% accurate. In engines, due to the friction generated as machine parts roll over another some of the chemical energy of the fuel is lost as heat. That is why machine parts are lubricated to reduce friction, and then energy loss.
Thus, 100% chemical energy does not yield 100% mechanical energy, as some are lost as heat.