are as given in the table below.

Usage in a day $($No$.$ of units$)$ No$.$ of days on which this usage occurred

$540$

$551$

$564$

$576$

$589$

$5911$

$6010$

$615$

$622$

$632$

$640$

Total $50$

The item is procured at Rs$.50$ per unit. But, if it is not used during the day, it gets deteriorated and can be sold at a salvage price of only Rs$.15$ the next day. However, if the item is not available in the required quantity on any day, it has to be procured from elsewhere at a premium of Rs$.25$ per unit. What should be the optimal stocking policy for this item.

$7.$ The following table contains figures on the monthly volume and unit costs fo