Question-5. It takes 6 minutes to load and 4 minutes to unload a machine. Inspection, packing, and travel between machines totals 4 minutes. Machines run automatically for 30 minutes. Operators cost $20 per hour; machines cost $50 per hour. a. What is the maximum number of machines that can be assigned to an operator without creating machine idle time? b. What is the number of machines that minimizes the cost? c. If three machines are assigned to an operator, what will be the cost per unit produced? d. If the cost per machine is unknown, for what range of values Cm will the optimum assignment remain the same