The marketing of a company's vehicles is carried out from 4 distribution centers to 3 direct sales points. Unit transportation costs (dollars), production (units) and monthly demand (USD) are represented in the following table. How should the shipment be in such a way that the transport cost is minimal? source/destinati point 1 point 2 point 3 production on center 1 $200 $150 $180 300 center 2 $130 $170 $210 350 center 3 $180 $200 $175 200 center 4 $170 $160 $185 150 requirements 250 350 350