Problem 21.4A (Static) Determining the Most Profitable Product Given Scarce Resources (L021-1, L021- 2, L021-3. L021-4) Insiteful Instruments produces two models of binoculars. Information for each model is as follows: Model 100 Model 101 Sales price per unit is 200 $ 215 Costs and expenses per unit: Direct materials $ 51 $ 38 Direct labor 33 30 Manufacturing overhead (applied at the rate of $18 per machinehour, 1/3 of which is fixed and 2/3 variable) 36 72 Variable selling expenses 30 15 Total costs and expenses per unit 150 155 Profit per unit $ 50 $ 60 Machinehours required to produce one unit 2 4 1 Total manufacturing overhead amounts to $180,000 per month, one-third of which is fixed. The demand for either product is sufficient to keep the plant operating at full capacity (10,000 machine-hours per month). Assume that only one product is to be produced in the future. a. Prepare a schedule showing the contribution margin per machine-hour for each product. b. Which of the two products should be discontinued