28.8 A firm hires labor in a perfectly competitive labor market. Its current profit-maximizing hourly output
is 100 units, which the firm sells at a price of $5 per unit. The marginal physical product of the
last unit of labor employed is 5 units per hour. The firm pays each worker an hourly wage of $15.
(See pages 626 and 633. a. What marginal revenue does the firm earn from sale of the output produced by the last
worker employed? b. Does this firm sell its output in a perfectly competitive market?

All other questions from the textbook including 28-1, 28-2, 28-4, 28-12, 31-4 and 31-10