In this task, you are given a question and a corresponding answer. Your task is to generate a fact statement that is useful in answering the given question.
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Question: Question: If a rub two rocks together after awhile they will start to? Answer: Get smooth.

Answer: contact between rocks over long periods of time causes rocks to smooth


Question: Question: What resources can be used over again? Answer: sustainable.

Answer: renewable resources can be used over again


Question: Question: An plant that requires lots of watering would do better in? Answer: a lush elm-filled area.

Answer:
a forest environment receives more rainfall than a desert