Given a fact, create a question that can be answered using the fact. Construct the question such that it is unambiguous, has a unique answer and the answer can be given using the fact.
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Question: Fact: the number of rings in a tree trunk can be used to estimate the age of the tree

Answer: If a tree is being discussed and those talking want to know its age, they will?


Question: Fact: the mantle is a layer of the Earth

Answer: The mantle is?


Question: Fact: wildfire is when a forest catches fire

Answer:
When a wildfire happens what catches fire?