2. Black Ridge Refining extracts minerals from ore mined at two different sites in Utah. Each ton of ore type 1 contains 15% copper, 20% zinc and 15% magnesium. Each ton of ore type 2 contains 25% copper, 25% zinc and 10% magnesium. Ore type 1 costs $90 per ton and ore type 2 costs $120 per ton. Black Ridge would like to buy enough ore to extract at least 8 tons of copper, 6 tons of zinc, and 5 tons of magnesium in the least costly manner. a) Use the graphical approach to solve this LP problem. b) Formulate a spreadsheet model and use Solver to solve this LP problem. c) Based on the sensitivity report, how much would it cost the company to get one more ton of copper? Explain