3. A manufacturer of pharmaceutical products analyzes a specimen from each batch of a product to verify the concentration of the active ingredient. The chemical analysis is not perfectly precise. Repeated measurements on the same specimen give slightly different results. Suppose we know that the results of repeated measurements follow a normal distribution with mean equal to the concentration and standard deviation = 0.0058 grams per dose (That the mean of the population of all measurements is the true concentration says that the measurement process has no bias. The standard deviation describes the precision of the measurement). The laboratory conducts 4 measurements for the active substance of the new medication Alkil-U, finding a mean of 0.9419 grams per dose. (a) Find the margin of error of a 95% confidence interval for the average concentration of the active substance in Alkil-U. (b) Determine (and interpret) the 95% confidence interval for the average concentration of the active substance in Alkil-U. (c) Determine how large a sample must be in order to have the same margin of error but with 99% confidence