In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.

Q: All insects have _ body sections, the head , thorax , and abdomen.

A: three
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Q: Pets also track in pollen, and _ out of every ten people is allergic to cat or dog dander.

A: one
****
Q: Yellow fever begins suddenly after an incubation period of three to _ days.

A:
five
****