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: A plum tree's purple leaves uses light energy to? Answer: create nourishment.

Answer: a leaf performs photosynthesis

Question: Question: Which is the likeliest part of a pencil to have been mined? Answer: the lead.

Answer: pencil lead contains mineral graphite

Question: Question: Sarah has one piece of wood that is smooth and polished and another that is rough and unfinished. Which of the following is true? Answer: the unfinished wood will generate more heat than the other while rubbed over the floor.

Answer:
as the roughness of something increases , the friction of that something will increase when its surface moves against another surface