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A market has a demand function D(p) = 22-P. There is a non discriminating monopolist on this market. The monopolist also has an opportunity to enter the world market if she pays fixed entry costs F. Given entry, she is able to sell any amount of product on the world market at a fixed world price. The total cost function is TC(q) = q + 10q + 4. Find the world price given that the monopoly sells 80% of product on the external market. What are the possible values of F