Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Q: Hydras and sea anemones are examples of apolyp.

A: Hydras and sea anemones are examples of what form?
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Q: Lead sulfate is the white solid that forms on corroded battery terminals.

A: What is the white solid that forms on corroded battery terminals?
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Q: Meteorites are often comprised of remnants of the earliest material that formed in the solar system.

A:
What astronomical phenomenon is often comprised of remnants of the earliest material that formed in the solar system?
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