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: Couples spend ____ billion dollars a year on infertility treatments.

Answer: two


Question: Warthogs also sport ____ sharp tusks.

Answer: four


Question: People marry young in Yemen, females as teenagers, and have an average of ____ children.

Answer:
seven