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: Flat screens come in ____ varieties, analog and digital.

Answer: two


Question: Some people routinely sleep only ____ hours a night but feel fine during the day.

Answer: four


Question: Most sea urchins possess ____ pairs of external gills, located around their mouths.

Answer:
five