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: Warthogs also sport ____ sharp tusks.

Answer: four


Question: Numbers can be positive or ____ only.

Answer: zero


Question: Negation is a total inverse for all ____ addition operators.

Answer:
three