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.

Fact: food is irradiated for space travel. 
Question: what food is required for space travel?
irradiated.

Fact: Mammals generate heat mainly by burning calories. 
Question: Mammals generate heat mainly by what?
burning calories.

Fact: Excel or Cricket can be used to display percents. 
Question: What can be used to display percents?

Excel or Cricket.