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: Maps have ____ or more bar scales, each in a different unit of measure.

Answer: three


Question: Spiritual slavery comes in ____ forms.

Answer: two


Question: Common iron is a mixture of ____ isotopes.

Answer:
four