Country A has 2000 units of labor and can produce two goods, manufactures and food. A's producers take 2 units of labor to produce one unit of manufactures and 5 units to produce one food unit. Country B has 2500 units of labor and takes 5 units of labor to produce one unit of manufactures and 10 units to produce one unit of food. At what price of food in terms of manufactures would A and B respectively supply food? Would trade take place in between A and B in David Ricardo's world? How many manufactures could A supply?