(40 points) We have mines A, B, C, and D which produce 30, 3E}, 60, and 50 tons respectively. We have cities q, r, and s which demand 40, 4D, 55 tons respectively. The transportation costs are as follows, with units of thousands of dollars per ton. _|--- We also have the requirement that every ton must be1 shipped to some city. Cities will dispose of excess at costs of 2, 1, and 3 thousand dollars per ton respectively. Set up but do not solve an LP to minimize total costs. Dene any variables that you use. Make sure you include all necessary parts of an LP. You can write mathematically (notation such as + - - - + is acceptable}