A commodity has a demand function modeled by p = 106 - 0.5x and a total cost function modeled by C = 40x + 39.75, where x is the number of units. (a) What unit price (in dollars) yields a maximum profit? $ per unit (b) When the profit is maximized, what is the average cost (in dollars) per unit? (Round your answer to two decimal places.) $ per unit