Using the approximation for finding the optimal policy for the stochastic single-period model with a setup cost

Question:

Using the approximation for finding the optimal policy for the stochastic single-period model with a setup cost when demand has an exponential distribution, find this policy when

and the costs are
Holding cost = 40 cents per item,
Shortage cost = $1.50 per item,
Purchase price = $1 per item,
Setup cost = $10.
Show your work, and then check your answer by using the corresponding Excel template in your OR Courseware.