"External Costs: Use the data in the table to answer the following questions:

"External Costs: Use the data in the table to answer the following questions: Marginal Private Benefit Marginal Private cost Marginal social cost (supply) $0 4 5 6 7 8 9 10 11 12 13 a. What is the external cost per unit of production? b. What level is produced if there is no regulation of the externality? c. What level should be produced to achieve economic efficiency? d. Calculate the dollar value of the net gain to society from correcting the externality."