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: Reds can benefit from ____ to nine years' aging .

Answer: seven


Question: Aardvarks have ____ toes on the front feet and five toes on their back feet.

Answer: four


Question: Catalysts are specific for only ____ or two reactions.

Answer:
one