W$1-1.($Raw Material Acquisition$)$ For its weekly operations, XYZ receives raw materials from two sources using large tank truck. Each truckload from Eco Petro Ltd contains $2$ tons of Raw Material A and $2$ tons of Raw Material B at a cost of $$20,000.$ Each truckload from Clean NRG contains $1$ ton of Raw Material A and $3$ tons of Raw Material B at a cost of $$15,000.$ XYZ requires at least $8$ tons of Raw Material A and at least $12$ tons of Raw Material B per week. XYZ is to determine how many truckloads should be purchased per week from each source. Formulate and solve a LP that minimizes the XYZ total costs of acquiring the raw materials.