For this question, we return to Pat$$s$,$ one of the Philadelphia cheesesteak restaurants mentioned in

Problem Set #$8$ about market share analysis. Cheesesteak service at Pat$$s is limited to a single

walk$-$up window: as a customer, you get into a single$-$file line and, upon reaching the service

window, you order your sandwich, pay for it$,$ receive it$,$ and leave$\mathrm{.}1$ Suppose, on average, that

$48$ customers arrive per hour, while the average service time per customer is $40$ seconds. Assume

that the single$-$channel $($M$/$M$/1)$ queueing model is appropriate for this scenario.