In a standard dissolution test for tablets for a particular drug product, the manufacturer must obtain the dissolution rate for a batch of tablets prior to release of the batch. Suppose that the dissolution test consists of assays for 24 randomly selected individual 25 mg tablets. For each test, the tablet is suspended in an acid bath and then assayed after 30 minutes. The results of the 24 assays are given here.

19.5 19.7 19.7 20.4 19.2 19.5 19.9 19.2 20.1 19.8 20.4 19.8 19.3 19.7 19.5 20.6 20.4 19.9 19.6 20.8 19.6 19.5 20.0 19.8

a) [MINITAB] Does the data appear to be a random sample from a normal distribution? Include the relevant Minitab plot/output, explain how you use it to answer this question, and provide your conclusion.

b) Find the point estimate of the mean dissolution rate of the tablets of this drug.

c) Estimate the mean dissolution rate of the tablets of this drug using a 99% confidence interval. Interpret the interval.

d) Is there significant evidence that the batch of pills has a mean dissolution rate less than 20 mg (which corresponds to 80% of the labeled amount in the tablets)?

e) Find and interpret the 99% lower confidence bound for the mean dissolution rate of the tablets of this drug.

f) Find and interpret the 99% upper confidence bound for the mean dissolution rate of the tablets of this drug.