2. Consider a town with two people, Bill and Ted. Bill's demand for tennis courts is given by Q = 30 - 5P and Ted's demand for tennis courts is given as Q = 12 - 2P. The marginal cost of providing tennis courts is constant at $3. a. Suppose the tennis courts are a private good. Derive the market demand curve (social marginal benefit curve) and find the equilibrium quantity. Horizontal summation is done for private goods. 30 - 5P = 12 - 2P 30 - 3P = 12 -3P = -18 P = 6 b. Suppose the tennis courts are a public good. Derive the social marginal benefit curve and find the optimal quantity of the public good