Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.
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Question: Question: The frequency of a wave is the reciprocal of what other attribute of the wave? Answer: period

Answer: The period of a wave and its frequency are reciprocals of each other.

Question: Question: What are flightless birds that are strong swimmers and spend much of their time in the water? Answer: penguins

Answer: Penguins are flightless birds that are strong swimmers and spend much of their time in the water.

Question: Question: What characteristic of reptile eggs allows them to be laid on land instead of in water? Answer: they are amniotic

Answer:
Reptile eggs are amniotic, so they can be laid on land instead of in water.