In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
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Question: Weasels reaching _ to six years are regarded as fully mature.

Answer: five


Question: Aquatic adults have prominent red reathery gills, are large, and have _ toes on each foot.

Answer: four


Question: Humans host _ species of louse, the head louse , the body louse and the pubic louse .

Answer:
three