You have been called in as a consultant to set up a Kanban control system. The first thing to do is to determine the number of Kanban card sets needed. Your research shows that the expected demand during lead time for a particular component is 150 per hour. You estimate the safety stock should be set at 25 percent of the demand during lead time. The tote trays used as containers can hold 8 units of stock, and the lead time it takes to replenish an order is 2 hours. Which of the following is the number of Kanban card sets necessary to support this situation? a. 42
b. 47
c. 68
d. 89
e. 94