$8.(20$ points$)$ Dunkin$$ Donuts at Vestal Parkway has one drive$-$through window. An average of $12$ customers per hour arrive at the store but only $80\%$ of the customers are eventually waiting at the window due to the long waiting line. It takes an average of $5$ minutes to serve a customer. Assume that interarrival and service times are exponential. Develop an Excel$-$based Monte Carlo Simulation model to evaluate the following performance metrics. Notes: Please write down your

answers in this exam and submit your Excel file via DropBox in BrightSpace.

$($a$)$ Average Total Time in the System $(10$ pt$)$

$($b$)$ Average Waiting Time in the Queue $(10$ pt$)$

$($c$)$ Average Customers in the System $(10$ extra pt$)$

$($d$)$ Average Customers in the Queue $(10$ extra pt$)$