help fast pls$!$ Reorder Point. Assume that for placing an order from a supplier, the lead time L$=20$ days, the daily demand is d$=20$ units, service level $($the probability that they can meet the demand during the lead time$)$ SL$=0\mathrm{.}99,$ standard deviation of the demand during the lead time is $\backslash$sigma $=20.$ How much should be the safety stock? $223\mathrm{.}523\mathrm{.}746\mathrm{.}6446\mathrm{.}6$