Consider the graph below, illustrating a positive externality. Price $46 $38 $30 $22 D2 = marginal social benefit $14 D.= marginal private benefit 27 Quantity Positive externality graph (text description +) a. What is the market equilibrium quantity? b. What is the efficient quantity? c. What is the efficient price? Do not include the $ in your answer. d. If the government wants to use a Pigovian subsidy to bring about the efficient level of output, what should the value of the subsidy be (per unit)? Do not include the $ in your