2. The Fagersta Steelworks currently is working two mines to obtain its iron ore. This iron ore is shipped to either of two storage facilities. When needed, it then is shipped on to the company's steel plant. The diagram below depicts this distribution network, where M1 and M2 are the two mines, S1 and S2 are the two storage facilities, and P is the steel plant. The diagram also shows the monthly amounts produced at the mines and needed at the plant, as well as the shipping cost and the maximum amount that can be shipped per month through each shipping lane. 40 tons produced MI $2,000/ton 30 tons max. $1,700/ton 30 tons max. $1,600/ton 50 tons max. S1 $400/ton 70 tons max. $800/ton 70 tons max. 100 tons needed 60 tons produced M2 $1,100/ton 50 tons max. G Management now wants to determine the most economical plan for shipping the iron ore from the mines through the distribution network to the steel plant. a. Identify all the requirements that will need to be expressed in fixed-requirement constraints. b. Express this model in algebraic form. c. Formulate and solve a linear programming model for this problem on a spreadsheet. (Use Excel)