Problem $12-21($Algo$)$

Demand for walnut fudge ice cream at the Sweet Cream Dairy can be approximated by a normal distribution with a mean of $20$ gallons

per week and a standard deviation of $3\mathrm{.}0$ gallons per week. The new manager desires a service level of $90$ percent. Lead time is two

days, and the dairy is open seven days a week. $($Hint$.$ Work in terms of weeks.$)$

Use Table B and Table B$1.$

a$-1.$ If an ROP model is used, what ROP would be consistent with the desired service level? $($Do not round intermediate calculations.

Round your final answer to $2$ decimal places.$)$

Answer is complete but not entirely correct.

$37\mathrm{.}62$ gallons

a$-2.$ How many days of supply are on hand at the ROP, assuming average demand? $($Do not round intermediate calculations. Round

your final answer to $2$ decimal places.$)$

Answer is complete but not entirely correct.

Days

$16\mathrm{.}00$

b$-1.$ If a fixed$-$interval model is used instead of an ROP model, what order size would be needed for the $90$ percent service level, with

an order interval of $5$ days and a supply of $8$ gallons on hand at the order time? $($Do not round intermediate calculations. Round your

final answer to the nearest whole number.$)$

Answer is complete and correct.