the competitive retail price for a stereo system is $300. retail stores normally have a margin of 30% for such items. wholesalers normally have a margin of 20% for such items. the manufacturer’s price is unknown. what steps should be taken to determine the manufacturer’s highest price?

In the market for lock washers, a perfectly competitive market, the current equilibrium price is $5 per box. washer king, one of the many producers of washers, has a daily short-run total cost given by tc = 190 + 0.20q + 0.0025q2, where q measures boxes of washers. washer king's corresponding marginal cost is mc = 0.20 + 0.005q. how many boxes of washers should washer king produce per day to maximize profit?