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Question 10. Consider the market for potatoes. Farmers use a fertilizer which enters the water system and has harmful effects. Suppose the private supply curve is given by P = 20 + Q and the private demand curve is given by P = 300 3Q, where Q is the units of potatoes. Suppose that potato production also has a marginal external cost of $40. a) What is the market equilibrium quantity of potatoes? b) Is the above quantity the socially optimal quantity of production? Why or why not? c) Draw the above graphs labelling, consumer surplus, producer surplus, external costs and deadweight loss when producing at the competitive market equilibrium. Calculate the external cost and deadweight loss at the market level of production