Given a sentence, fill out the missing word with a 'no' or a number (between zero and ten). You should write the numbers with english alphabet, like: four instead of 4.
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Question: Potential energy is divided into ____ different types of energy.

Answer: three


Question: Soy products contain ____ known classes of anti-cancer agents, including phytoestrogens.

Answer: five


Question: China has more than ____ times as many people as the United States.

Answer:
four