In this task, you are given a sentence and a question, you would be asked to create the answer which is contained in the sentence provided.
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Question: Sentence: Air pressure it decreases as altitude increases. Question: How does air pressure change as altitude increases?

Answer: it decreases


Question: Sentence: Volcanic gases helpe to form the atmosphere on earth. Question: What did volcanic gases help to form on earth?

Answer: atmosphere


Question: Sentence: Removes unwanted substances does water treatment do to water. Question: What does water treatment do to water?

Answer:
removes unwanted substances