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

Q: Tobacco kills four million people a year, one death every _ seconds.

A: eight
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Q: Frozen grafts can have a shelf life of up to _ years.

A: five
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Q: Sheep have _ skin pouches, or scent glands.

A:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
three
****
