Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: Seismic waves prove the inner core it is solid.

Answer: What do seismic waves prove about the inner core?

Question: Metallic bonds gives a coil of copper wire the ability to conduct electricity well.

Answer: What gives a coil of copper wire the ability to conduct electricity well?

Question: Prokaryotic cells have a cell wall outside their plasma membrane.

Answer:
Prokaryotic cells have what structure outside their plasma membrane?