Annual demand for a particular halogen bulb is $4500$ at a business that operates $300$ days per year. The cost per order $$180$ and the holding cost per unit per year is $$4\mathrm{.}2.$ The stockout cost is $$40/$unit$.$ The lead time is $20$ days.

The demand during lead time follows a normal distribution with a mean of $300$ and a standard deviation of $40.$

What is the service level if the safety stock is $15?($Compute the standard normal variate to an accuracy of $3$ decimal digits$)$ Report as a whole number.

What is required reorder point for a service level of $95\%?$