Suppose your firm's total product curve includes the following data: One worker can produce 8 units of output; two workers, 20 units; three workers, 34 units; four workers, 50 units; five workers, 60 units; six workers, 70 units; seven workers, 76 units; eight workers, 78 units; and nine workers, 77 units.
a. What is the marginal product of the seventh worker?
b. When does the law of diminishing product set in?
c. Under these conditions, would you ever choose to employ nine workers?