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: The face of the sphinx has changed from? Answer: wearing away.

Answer: wind and rain cause erosion


Question: Question: What's a good way to heat up inside after ice skating on a frozen lake? Answer: set fire to some natural gas.

Answer: natural gas is a source of heat by burning


Question: Question: Ligers are less likely to thrive when there is? Answer: famine.

Answer:
an animal being born when food is available has a positive impact on that animal 's health