3. A clinical trial was conducted in which 50 patients were randomly assigned to one of five cholesterol -reducing drug regimens . Three of the drug regimens involved the same drug administered as 20 mg once per day (1time ), 10 mg twice per day (2times ), or 5 mg four times per day (4times ). The two remaining drug regimens (drugD and drugE ) represented competing drugs . Previous studies have shown that cholesterol reduction is approximately normally distributed with equal variance across patients receiving a range of different cholesterol -reducing drugs . The data set for the trial is in the Data folder in A21 Contents , is called Q3_CHOL , and has two variables : tit (indicating drug regimen ) and response (indicating cholesterol reduction in mmol /1). Use these data to answer the questions below. Assume a=0.05 a. Create a box & whisker plot to compare the cholesterol reduction levels across the five treatment groups. Comment on the pattern you see in cholesterol reduction across the treatment groups. [2 Marks ] b. Run the appropriate statistical test to determine if there is a significant difference in the cholesterol reduction levels across the five treatment groups. What do you conclude from running this test? Provide the calculation and/or SP55 output to support your answer. [1 Mark ] c. You decide to conduct post-hoc tests to follow up on the results. Choose an appropriate post-hoc test to determine which drug regimen you would select if your goal was to reduce the cholesterol level in your patients. Explain your choice. [2 Marks ]