In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
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Question: Southern moles are six to seven inches long and weigh _ to four ounces.

Answer: three


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

Answer: three


Question: Natural selenium contains _ stable isotopes.

Answer:
six