18. Assuming that demand is normally distributed (mean of 250 units per period and a standard deviation of 75 units per period) and a lead time of 3 periods, what reorder point will guarantee that no more than 5 percent of order cycles will have one or more stockouts? (Choose the best answer.)

a. 900 units

b. 1,000 units

c. 1,100 units

d. 1,200 units