Given a statement, generate a question such that the answer is contained in that statement.
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Question: The volume of an object can be used to measure that object.

Answer: What can be used to measure an object?

Question: Detailed observation of stars needs a telescope.

Answer: What type of telescope is required for a detailed observation of stars?

Question: Small-sized viviparous mammals evolved by Jurassic times.

Answer:
When did small-sized viviparous mammals evolve?