4.1 Here are average cycle times for five workcenters. State which are bottlenecks, nonbottlenecks, and capacity-constrained resources. (5) Processing time Set up time 1 2 3 4 5 Processing time Set up Idle time Processing time Set up Idle time Processing time Set up time Idle time Processing time Set up Idle time 4.2 The X Y plant manufactures two different products: X and Y. Selling prices and weekly market demand 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. Product X Product Y Resources: A, B, C (one each) Availability: 4800 min/week Operating expenses: R24 000/week R380/unit 200 units/week R400/unit 100 units/week C =30 min/unit A =40 min/unit RM-1 R120/UNIT B = 30 min/unit RM-2 R80/UNIT C =30 min/unit B =30 min/unit RM-3 R80/UNIT Process times for each task are shown in the diagram. Each machine is available 4800 minutes per week. There are no Murphys (major opportunities for the system to foul up). Set up and transfer times are zero. Demand is constant. 4 Operating expenses (including labor) total a constant R24 000 per week. Raw materials are not included in weekly operating expenses. a) Where is the constraint in this plant? NB: Show all the steps. (12) b) What product mix provides the highest profit? (10) c) What is the maximum weekly profit this plant can earn