Both Canada and the United States produce lumber and footballs with constant opportunity costs. The United States can produce either 10 tons of lumber and no footballs, or 1,000 footballs and no lumber, or any combination in between. Canada can produce either 8 tons of lumber and no footballs, or 400 footballs and no lumber, or any combination in between. a. Draw the U.S. and Canadian production possibility frontiers in the accompanying graphs, with footballs on the horizontal axis and lumber on the vertical axis. b. In autarky, if the United States wants to consume 500 footballs, how much lumber can it consume