Organs , fins is the correct answer
<span>The generally accepted parts of modern cell theory include: All known living things are made up of one or more cells. All living cells arise from pre-existing cells by division. The cell is the fundamental unit of structure and function in all living organisms. hope this helps but you should be more specific in the future</span>
He could race multiple cars with different weight added on them and do multiple races (just to be sure) and see if his theory was correct, if not he should right down what he has learned from his experience! :D
-You'll never learn if u don't try ;)