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: Hydrogen gas is generated by the reaction of nitric acid and elemental iron else. Question: Hydrogen gas is generated by the reaction of nitric acid and what else?

Answer: elemental iron

Question: Sentence: Correlation is the comparison of two factors within a population. Question: What is the comparison of two factors within a population?

Answer: correlation

Question: Sentence: The rate of decay of carbon-14 does remains stable over time. Question: The rate of decay of carbon-14 does what over time?

Answer:
remains stable