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 cup of cold coffee will warm up when heat is applied such as through? Answer: an electrical plate.

Answer: a hot plate is a source of heat


Question: Question: An example of a fossil is a paw print in what? Answer: hard stones.

Answer: An example of a fossil is a paw print in rock


Question: Question: A stone is weathered into sand in about? Answer: a millennia.

Answer:
weathering usually occurs over a period of many years