Given this information: Lead-time demand = 640 pounds Standard deviation of lead time demand = 40 pounds (Assume normality.) Acceptable stock out risk during lead time = 4 percent Use Table. a. What amount of safety stock is appropriate? (Round your answer to the nearest whole number.) Safety stock units b. When should this item be reordered? (Round your answer to the nearest whole number.) ROP units c. What risk of stock out would result from a decision not to have any safety stock?