$19.$ Given this information: Expected demand during lead time $=300$ units Standard deviation of lead time demand $=30$ units Determine each of the following, assuming that lead time demand is distributed normally: a$.$ The ROP that will provide a risk of stockout of $1$ percent during lead time. b$.$ The safety stock needed to attain a $1$ percent risk of stockout during lead time. c$.$ Would a stockout risk of $2$ percent require more or less safety stock than a l percent risk? Explain. Would the ROP be larger, smaller, or unaffected if the acceptable risk were $2$ percent instead of $1$ percent? Explain. a