Turn the given fact into a question by a simple rearrangement of words. This typically involves replacing some part of the given fact with a WH word. For example, replacing the subject of the provided fact with the word "what" can form a valid question. Don't be creative! You just need to rearrange the words to turn the fact into a question - easy! Don't just randomly remove a word from the given fact to form a question. Remember that your question must evaluate scientific understanding. Pick a word or a phrase in the given fact to be the correct answer, then make the rest of the question. You can also form a question without any WH words. For example, "A radio converts electricity into?"
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Question: Fact: Water must not be polluted to be safe.

Answer: What can happen to water to make it unsafe?


Question: Fact: Using gasoline causes global warming.

Answer: What causes global warming?


Question: Fact: Mollusks have a circulatory system with one or two hearts that move blood into vessels called arteries.

Answer:
Mollusks have a circulatory system with one or two hearts that move blood into what?