(Transportation problem) Suppose Texas, California, and Alaska each produce a million barrels of oil; 800,000 barrels are needed in Chicago at a distance of 1000, 2000, and 3000 miles from the three producers, respectively; and 2,200,000 barrels are needed in New England 1500, 3000, and 3700 miles away. If shipments cost one unit for each barrel-mile, what linear program with five equality constraints must be solved to minimize the shipping cost?