Question 2 (Total = 15 marks) The private marginal benefit for commodity X is given by 25-5X, where X is the number of units consumed. The private marginal cost of producing X is constant at $10. For each unit of X produced, an external cost of $5 is imposed on members of society. a. In the absence of any government intervention, how much X is produced? (2 marks) b. What is the efficient level of production of X? (3 marks) c. What is the gain to society involved in moving from the inefficient to the efficient level of production? (2 marks) d. Suggest a Pigouvian tax that would lead to the efficient level. How much revenue would the tax raise? (2 marks) e. Draw a graph to illustrate your answers in parts (a) - (d); using the appropriate labels. (6 marks)