Q7. Two-part tariffs [30 points) A monopolist face; two consumers with the following demand curves: P1 = 10 91 P2 = 8 92 The monopolist has no cost of production. It can charge an entry fee f and a per-unit price 1). First, we suppose p 2 MC = U and the monopolist only charges an entry fee. a. Given the monopolist serves both customers, what is the profit maximizing f? b. Can the monopolist make more money by charging a higher entry fee? Now suppose the monopolist wants both consumers to enter but is willing to change the price p (and therefore CS changes). Given both consumers enter and consume nonnegative quantities, the monopolist's profit is 'r'r =p(18 - 219), subject to the constraint (which I will call (IRD that all consumers have nonnegative surplus after entry fees: (8 -p)2 (rmTfzo c. Calculate the profit-maximizing p and f. d. Explain in words which scheme (parts a, b, or c) is efficient from a simple social welfare perspective