High Plains Inc. manufactur High Plains Inc, manufacturers furniture in North Dakota. High Plains receives its wood from a lumber yard in Calgary. The lead time for orders is 3 weeks. One of their board costs $15 per unit and the holding cost for this board is $0,5 per week. They manage their Inventory to achieve a 99 percent in-stock probability. Weekly demand is for 250 boards with a standard deviation of 200. Use Table 115 Answer is complete but not entirely correct. How many boards do they have on on order on average ?