6.22 Athletes take oxygen. We often see players on the sidelines of a football game inhaling oxygen. Their coaches think this will speed their recovery. We might measure recovery from intense exertion as follows: Have a football player run 100 yards three times in quick succession. Then allow three minutes to rest before running 100 yards again. Time the final run. Describe the design of two experiments to investigate the effect of inhaling oxygen during the rest period. One of the experiments is to be a completely randomized design and the other a matched pairs design in which each student serves as his or her own control. Twenty football players are available as subjects. In both experiments, carry out the randomization required by the design.