Write a correct answer to the given question based on its associated fact. Make sure that your answer is contained in the associated fact. Don't be creative and introduce any new word that is not mentioned in the associated fact! Remember that the associated fact has been rearranged to form the question. So, the correct answer words must lie within the associated fact. The correct answer can be a word, phrase, or even a sentence.
--------
Question: Fact: a camera records light. 
Question: What records light?

Answer: a camera.


Question: Fact: diatomes have varied life cycles. 
Question: what have varied life cycles?

Answer: diatomes.


Question: Fact: The volume of a physical thing can be used to describe the size of that physical thing. 
Question: What can the volume of a physical thing in math describe?

Answer:
its size.