How to solve this using marginal analysis ( Q= l + f (u-l) ) Milk is a perishable product. Every week the store needs to decide how many bottles of milk to order from the supplier, and if the milk is not sold by the end of the week, the store has to dispose of it. The sales price is $5 and the purchase price is $3. The weekly demand for milk follows uniform probability distribution from 1,136 to 1,619 bottles. A tax of $1 for each bottle of expired milk disposed of. How will this affect the weekly optimal order size of the grocery store?