i need help with question number (2) and (3)

Suppose the marginal cost of television sets is constant at $100. The annual demand for television sets is given by Q = 200,000 - 500 P, where Q is the quantity sold per year and P is the price of television sets. a. Graph out the supply and demand curves in this market. (Recall that the supply curve is the same as the marginal cost curve.) b. If television sets are sold in a perfectly competitive market, how many would be sold, and at what price? c. Under what circumstances would the market equilibrium be efficient? The supply of candy is given by Qs = 20,000P where Qs is bags of candy supplied per year and P is the price per bag. The demand for candy is given by Qd = 150,000 - 30,000P a. Assuming that candy is sold in a competitive market, what is the equilibrium price and quantity? b. To discourage the consumption of candy, the government levies a tax on consumers in the amount of $1 per bag. What is the new equilibrium quantity? c. What is the impact of the tax on welfare in this market? The supply of paper is described by the following equation Qs = 5,000P where Qs is tons supplied per year and P is the price per ton. The demand for paper is given by Qd = 400,000 - 3,000P Production of paper generates an externality of $20 per ton produced. a. Assuming that paper is sold in a competitive market, what is the equilibrium price? How many tons of paper will be produced? b. How does the socially efficient annual output of paper compare to the equilibrium amount? (Is it higher, lower, or the same?) Explain your answer using a graph. c. Suppose the government wanted to levy a tax to get producers to sell the socially efficient amount of paper. How large should the tax be