Please Show how it is done using excel solver, step by step.

19. (20 points) FlexSteal, marketed as a miracle brush-on sealant and baldness cure, is manufactured at three plants that are struggling to keep up with the demand at the four regional centers. The cost to ship a truckload from each of the existing plants to the regional centers is shown in the table. Note that the capacity and the total demand are both measured in truckloads. Philadelphia Plant 1 89 Plant 2 120 Plant 3 95 Total Demand 350 Atlanta 75 88 82 350 Dallas 93 103 112 350 Los Angeles 115 93 98 350 Capacity 400 400 400 The supply chain manager has explored plant construction costs in two other cities as well as the cost to ship a truckload from each of the plants to the regional centers. The current plan is to build another plant with a capacity of 400 to allow room for sales growth. The construction cost for the new plants and cost to ship to each of the regional centers is shown here. Philadelphia Atlanta Dallas Los Angeles Cost to Build Plant A 94 78 95 95 $23,500 Plant B 95 88 88 94 $26,000 (a) (5 points) What is the lowest cost solution for the existing set of plants and regional centers? (b) (5 points) Setup objective function. (C) (10 points) Setup constraints