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5. (24 points) An industry consists of a dominant firm with costs C(Qd) = 80Qa and 20 identical fringe firms who compete competitively, each with costs C(q) = 100q + 5q2. Market demand is Q = 800 -3P where Q is the total quantity demanded. (i) (4 points) Derive the firm and industry supply of the fringe firms. (ii) (8 points) Draw the residual demand, residual marginal revenue for the dominant firm, and the industry supply of the fringe firms on the same graph labeling all intercepts and kink points. (iii) (8 points) Draw the MC for the dominant firm in the graph above showing where it intersects MR for the dominant firm, and indicate the profit maximizing price and quantity the dominant firm would choose. (iv) (4 points) What is the total fringe firm output and output of each of the fringe firms