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: if copper is exposed to a source of heat then that copper may easily become hot. 
Question: What can easily become hot if exposed to heat?

Answer: copper.


Question: Fact: Food can be cooked on metal. 
Question: Which surface can food be cooked on?

Answer: Metal.


Question: Fact: Adding salt to a liquid changes the nature of the liquid. 
Question: Adding salt to a liquid changes what aspect of the liquid?

Answer:
nature.