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: Sexual maturity occurs at ____ to four years for females and four to five years for males.

Answer: three


Question: Women have about ____ times as many foot problems as men.

Answer: four


Question: Manatees have only ____ neck vertebrae.

Answer:
six