Drywall for construction is made from a rock called gypsum. Gypsum is mined at the mine and shipped to the plant to be made into drywall board. There are four gypsum mines A, B, C, D, E There are 3 drywall plants 1, 2, 3 Production of the mines are as follows: A - 1,000 tones B - 10,000 tones C - 4,000 tones D - 6,000 tones E - 5,000 tones.

Demand for each plant is as follows: 1 - 3,000 tones 2 -15,000 tones 3 - 5,000 tones

The transportation cost matrix is as follows (per ton) 1 2 3 A $ 100.00 $ 100.00 $ 100.00 B $ 150.00 $ 50.00 $ 75.00 C $ 200.00 $ 50.00 $ 50.00 D $ 100.00 $ 100.00 $ 75.00 E $ 75.00 $ 75.00 $ 75.00

(1) You are tasked with finding the cheapest way to transport material from the mines to the plants. All demand of the plants must be met but not all production of the mines needs to be used. What is the transportation schedule for this network and its cost?

(2) Same numbers but plant 1 can ONLY process gypsum from mine C. How does this change the shipping schedule and cost? An equipment supplier has offered you a processing system that will allow plant 1 to process gypsum from any mine. At what price for the system would you be indifferent to its purchase by your firm?