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: In the puberty stage is a time of significant mental, emotional and social change. 
Question: What is a time of significant mental and emotional change?
puberty.

Fact: dogs require nutrients to grow and heal. 
Question: what requires nutrients to grow and heal?
dogs.

Fact: a car engine usually converts gasoline into motion and heat through a type of oxidation reaction. 
Question: how does a car engine usually convert gasoline into motion and heat?

oxidation reaction.