A humanitarian aid operation in Somalia requires supplies to be delivered to three inland locations named 1, 2, and 3, whose demands are 500, 600, and 450 tons respectively. The deliveries can come from any of three ports named A, B, and C. The shipping costs per ton from each port to each location are given below (in thousands of dollars).

  

The US can provide ports A, B, and C, which currently have no supplies, with 1100, 1200 and 1000 tons of supplies, respectively (all-or-nothing for each port). These fixed costs would be 20, 18, and 22 million dollars, respectively. 

Formulate and solve a linear optimization model to determine which ports to use and how to distribute the supplies in order to minimize the total cost.

From Ports A B C To Locations 1 2 3 43 88 103 105 75 95 75 60 90