Alice, Beth, and Carol are the only three demanders of a pure public good. Their demand functions are as follows: P a = 70 - G, P b = 110 - G, P c =...

Alice, Beth, and Carol are the only three demanders of a pure public good. Their demand functions are as follows:

     Pa = 70 - G,

     Pb = 110 - G,

     Pc = 130 - G.

G measures the number of units of the good and pi is the price in dollars. The marginal cost of the public good is a constant $190.