According to the Food and Drug Administration (FDA), a cup of coffee contains on average $115$ miligrams (mg) of caffeine, with the amount per cup ranging from $60$ to $180$ mg. Suppose you want to repeat the FDA experiment to obtain an estimate of the mean caffeine content in a cup of coffee correct to witin $3.6$ mg with $95$% confidence. How many cups of coffee would have to be included in your sample?

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