The MN plant manufactures two different products: M and N. Selling prices and weekly market demands are shown in the following diagram. Each product uses raw materials with costs as shown. The plant has three different machines: A, B, and C. Each performs different tasks and can work on only one unit of material at a time. Process times for each task are shown in the diagram. Each machine is available 3,600 minutes per week. There are no "Murphys" (major opportunities for the system to foul up). Setup and transfer times are zero. Demand is constant. Operating expenses (including labor) total a constant $12,000 per week. Raw materials are not included in weekly operating expenses. a. Which machine is the constraint in this plant? Machine A Machine C Machine B b. Which product mix provides the highest gross profit? (Hint: consider raw material cost but not operating expense) c. What is the maximum weekly net profit this plant can earn using the product mix from Part b? (Hint: consider operating expense and raw material cost)