In this task, you are given a question and answer for that. The answer will fill in the blank or will complete the unfinished question. Your task is to provide an explanation based on the given question or fill-in-the-blank statement, and answer.

Q: Question: Mike is digging for old rocks. Mike dig downs very, very shallow, and he expects the rocks there to be 
 Answer: younger

A: Therefore, deeper rock layers must be older than layers closer to the surface.
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Q: Question: When Katie was in the hospital with low blood pressure, she understood that the volume of her blood was 
 Answer: low

A: As blood volume in the body increases, blood pressure increases.
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Q: Question: Don is looking at electromagnetic waves, and sees that the one's he observing have lower frequencies. Don is able to know then that the photons have energy that is 
 Answer: lower

A:
In electromagnetic waves with higher frequencies, photons have more energy.
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