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4. Listed below are measured amounts of caffeine (mg per 12 oz of drink) obtained in one can from each of 15 brands of soft drinks. 34 34 34 45 41 51 55 36 47 41 53 54 38 41 47 a) Construct a 99% confidence interval estimate of the mean of the weights. Round the values to one decimal place. Construct a 90% confidence interval estimate of the mean of the weights. Round the values to one decimal place