In this task, you are given a question and an answer, you would be asked to create the sentence based on the Question-Answer provided. It should be contained within the Question-Answer provided.

Q: Question: Expansion of a gas into a vacuum is irreversible because the external pressure is measurably less than the internal pressure of the gas, and no states of what exist? Answer: equilibrium

A: Expansion of a gas into a vacuum is irreversible because the external pressure is measurably less than the internal pressure of the gas, and no states of equilibrium exist.
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Q: Question: The amniotic egg first evolved in what species? Answer: reptiles

A: The amniotic egg first evolved in reptiles.
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Q: Question: What is controlled by both genes and experiences in a given envionment? Answer: animal behaviors

A:
Animal behaviors are controlled by both genes and experiences in a given envionment.
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