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In a monopolistic competition market, assume the following AC = (nF/S) + c, P= c + (1/bn) where n is the number of firms, F is the fixed cost, S is the market size, c is the marginal cost, and b is a constant. b = 1/30,000, fixed cost F = $750,000,000, marginal cost c = $5,000 per automobile. Setting the average cost equal to price yields the following expression: AC=P n = [(1/b) x 5/F] 1/2 With three countries the size of the market S=6,250,000 and the number of firms n=15. Due to a trade war, one of the countries drops out of the market. The size of the market S=4,650,00. What is the number of firms given this lower size of the market. O 11 12 13 14 15