Given a scientific passage and an answer, generate a question for the given answer.

Q: Passage: Some people think that gravity moves food through the esophagus. If that were true, food would move through the esophagus only when you are sitting or standing upright. In fact, because of peristalsis, food can move through the esophagus no matter what position you are ineven upside down! Just don't try to swallow food when you are upside downyou could choke!. Answer: peristalsis

A: What process moves food through the esophagus no matter which position the body is in?
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Q: Passage: Climate is the most important factor in determining the type of soil that forms in a particular area. Answer: climate

A: What is the most important factor in determining the type of soil that forms in a particular area?
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Q: Passage: Compared to Earth, the solar system is a big place. But galaxies are bigger - a lot bigger. A galaxy is a very large group of stars held together by gravity. How enormous a galaxy is and how many stars it contains are impossible for us to really understand. A galaxy contains up to a few billion stars! Our solar system is in the Milky Way Galaxy. It is so large that if our solar system were the size of your fist, the galaxy's disk would be wider than the entire United States! There are several different types of galaxies, and there are billions of galaxies in the universe. Answer: milky way

A:
What galaxy is our solar system a part of?
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