Answer:
crops is a renewable resources, coal, natural gas and oil are not renewable as they will not last forever.
Easy. Answer is oxygen because it says which one was missing before any life was on earth. And in order to have life on earth you need oxygen!
:)
The answer is nitrogen fixation.
Hope this helps
B-Bioprocessing for forestry products.
A is your answer I believe because they do indeed provide a way to review other scientists work and or experiments
