Include correctly labeled diagrams. if useful or required, in explaining your answers. A correctly labeled diagram must have all axes and curves clearly labeled and must show directional changes. If the question prompts you to \"Calculate," you must show how you arrived at your nal answer. Copper is produced in a perfectly competitive market with an upward-sloping supply curve and a downward-sloping demand curve. Assume the production of copper results in liquid waste, which seeps into local rivers. The contaminated river water causes human illnesses and crop failures downstream. The marginal external cost from producing copper is constant across all quantities of copper produced. (a) Draw a correctly labeled graph of the copper market with the marginal social benet (MSB), marginal private benet (MPB), marginal social cost (MSC), and marginal private cost (MPC) curves, and show each of the following. (i) The market equilibrium quantity, labeled QM (ii) The socially efcient quantity, labeled QS (b) Suppose the demand for copper decreases. On your graph in part (a), show the deadweight loss at the new market equilibrium, shaded completely. (c) Suppose the government is considering levying a tax on copper. (i) What per-unit tax level would achieve the socially optimal quantity? (ii) Explain why a lump-sum tax on producers will not achieve the socially optimal quantity in the short run