Annual demand = 1000 units Ordering cost = $50/order Annual carrying cost = 35 percent Purchasing cost = $50 per unit for 0-99 $48 per unit for 100-299 $46 per unit for 300-599 $44 per unit for 600 or more a. What is the optimal order size that can minimize the total cost for the following question? (Find the closest answer) b. Suppose the current order size is 90 units per order. How much savings can we get if we switch order size from current order size (i.e., 90 units) to the optimal order size found in the previous question (i.e., Q42)? (Find the closest answer)