A group of students wants to perform an experiment to determine whether Brand A or Brand B deodorant lasts longer. One group member suggests the following design: Recruit 40 student volunteers 20 male and 20 female. Separate by gender, because male and female bodies might respond differently to deodorant. Give all the males Brand A deodorant and all the females Brand B. Have the principal judge how well the deodorant is still working at the end of the school day on a 0 to 10 scale. Then compare ratings for the two treatments.

a. Identify any flaws you see in the proposed design for this experiment.

b. Describe how you would design the experiment. Explain how your design addresses each of the problems you identified in part (a).