3.6 Ben swims 50,000 yards per week in his practices.

Given this amount of training, he will swim the 100-yard butterfly in 52.6 seconds and place tenth in a big upcoming meet. Ben’s coach calculates that if Ben increases his practice to 60,000 yards per week, his time will decrease to 50.7 seconds and he will place eighth in the meet. If Ben practices 70,000 yards per week, his time will be 49.9 and he will win the meet.

a. In terms of Ben’s time in the big meet, what is his marginal productivity of the number of yards he practices? Does the marginal product diminish as the practice yards increase?

b. In terms of Ben’s place in the big meet, what is his marginal productivity of the number of yards he practices? Does the marginal product diminish as the practice yards increase?

c. Does Ben’s marginal productivity of the number of yards he practices depend on how he measures his productivity, either place or time, in the big meet?