9.8. Dave's Fresh Catfish is a northern Mississippi farm that operates in the perfectly competitive catfish farming industry. Dave's short-run total cost curve is STC(Q) = 400 + 2Q + 0.5Q2, where Q is the number of catfish harvested per month. The corresponding short-run marginal cost curve is SMC(Q) = 2 + Q. All of the fixed costs are sunk. a. What is the equation for the average variable cost (AVC)? b. What is the minimum level of average variable costs? c. What is Dave's short-run supply curve? 9.9. Ron's Window Washing Service is a small business that operates in the perfectly competitive residential window washing industry in Evanston, Illinois. The short-run total cost of production is STC(Q) = 40 + 10Q + 0.1Q2, where Q is the number of windows washed per day. The corresponding short-run marginal cost function is SMC(Q) = 10 + 0.2Q. The prevailing market price is $20 per window. a. How many windows should Ron wash to maximize profit? b. What is Ron's maximum daily profit? c. Graph SMC, SAC, and the profit-maximizing quantity. On this graph, indicate the maximum daily profit. d. What is Ron's short-run supply curve, assuming that all of the $40 per day fixed costs are sunk? e. What is Ron's short-run supply curve, assuming that if he produces zero output, he can rent or sell his fixed assets and therefore avoid all his fixed costs? 9.10. The bolt-making industry currently consists of 20 producers, all of whom operate with the identical short-run total cost curve STC(Q) = 16 + Q2, where Q is the annual output of a firm. The corresponding short-run marginal cost curve is SMC(Q) = 2Q. The market demand curve for bolts is D(P) = 110 P, where P is the market price. a. Assuming that all of each firm's $16 fixed cost is sunk, what is a firm's short-run supply curve? b. What is the short-run market supply curve? c. Determine the short-run equilibrium price and quantity in this industry. 9.11. Newsprint (the paper used for newspapers) is produced in a perfectly competitive market. Each identical firm has a total variable cost TVC(Q) = 40Q + 0.5Q?, with an associated marginal cost curve SMC(Q) = 40 + Q. A firm's fixed cost is entirely nonsunk and equal to 50. a. Calculate the price below which the firm will not produce any output in the short run. b. Assume that there are 12 identical firms in this industry. Currently, the market demand for newsprint is D(P) = 360 2P, where D(P) is the quantity consumed in the market when the price is P. What is the short-run equilibrium price