The Energetic Company needs to make plans for the energy systems for a new building. The energy needs in the building fall into three categories: (1) electricity. (2) heating water, and (3) heating space in the build- ing. The daily requirements for these three categories (all measured in the same units) are Electricity Water heating Space heating 30 units 20 units 50 units The three possible sources of energy to meet these needs are clec. tricity, natural gas, and a solar heating unit that can be installed on the roof. The size of the roof limits the largest possible solar heater to 40 units, but there is no limit to the electricity and nat- ural gas available. Electricity needs can be met only by purchas- ing electricity (at a cost of $50 per unit). Both other energy needs can be met by any source or combination of sources. The unit costs are Water heating Space heating Electricity Natural Gas Solar Heater 3150 $110 570 5140 $100 590 The objective is to minimize the total cost of meeting the energy needs. (a) Formulate this problem as a transportation problem by con- structing the appropriate parameter table. DJ (b) Use the northwest comer rule to obtain an initial BF solu- tion for this problem. DI (e) Starting with the initial BF solution from part (b), interac- tively apply the transportation simplex method to obtain an optimal solution. D.1 (d) Use Vogel's approximation method to obtain an initial BF solution for this problem. DJ (e) Starting with the initial BF solution from part (d), interac- tively apply the transportation simplex method to obtain an optimal solution