4. Assume the following information for the United States and Mexico. The United States can produce a maximum of 600 bushels of barley or a maximum of 600 bushels of corn. Mexico can produce a maximum of 200 bushels of barley or 400 bushels of corn. Which country has a comparative advantage in the production of barley? Which country has a comparative advantage in the production of Corn? Show your work for the calculation of opportunity cost. (4 Points)