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: Allen is riding his bike on a path. The course ends up 1000 feet lower above sea level compared to the beginning. At which point is the air resistance lower? 
 Answer: at the beginning

A: At higher elevations, there is less air to press on a given area.
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Q: Question: A car with 4 cylinders is _____ than a car with 6 cylinders. 
 Answer: less powerful

A: The more cylinders a car engine has, the more powerful its engine can be.
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Q: Question: As we start sleeping our hearts pump slower which means blood flow 
 Answer: decreases

A:
Warming up exercises increases the blood flow to the muscles and increases the heart rate.
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