A small electric generating plant must decide how much low-sulfur (2%) and high-sulfur (6%) oil to buy. The final mixture must have a sulfur content of no more than 4%. At least 1200 barrels of oil are needed. Low-sulfur oil costs $18.50 per barrel and high-sulfur oil costs $14.70 per barrel. How much of each type of oil should the plant use to keep the cost at a minimum? What is the minimum cost?