Parker$$s purchasing agent, Raktim Pal, submits an order release for LCD screens once every $4$ weeks.

The company$$s annual requirements total $500$ units $(2$ per working day$),$ and Parker$$s per unit cost is

$$1,500.($Because of Parker$$s relatively low volume and the quality focus$$rather than volume focus$$ of

many of Parker$$s suppliers, Parker is seldom able to obtain quantity discounts.$)$ Because Foxy promises

delivery within $1$ week following receipt of an order release, Parker has never had a shortage of LCDs$.$

$($Total time between date of the release and date of receipt is $1$ week or $5$ working days.$)$