Suppose Dexter and Amy are the only members of a community that is trying to determine how much of a public good should be produced. Dexter's (inverse) demand curve is given by P = 50-5Q, while Amy's (inverse) demand curve is given by P = 150-15Q, where P is price or marginal benefit and Q is the quantity of the good. The marginal cost of producing the public good is constant at $80. Amy will vote for the efficient quantity of the public good if the price to her is:
a. $20.
b. $40.
c. $60.
d. $80.
