Answer: D Although the total energy remains constant, nonrenewable fuels convert chemical energy into forms that are difficult or impossible to use again.
Explanation:
The first law of thermodynamics says that energy can neither be created nor destroyed; energy can only be transferred or changed from one form to another.
Answer:
the branch of science concerned with the nature and properties of matter and energy
I think it "Death rate" but I am not very sure though.