same customer arrival rate. Explain the reason using Little's Law.

Example $2$: The Ted Williams Tunnel travels under the Boston harbor, connecting East Boston to South Boston. The Massachusetts Transit Authority $($MTA$)$ tries to modulate the number of toll booths that are open at any point in time so that the average number of vehicles waiting at the tolls $($including those at the booths$)$ never exceeds $20$ vehicles. For instance, all six booths are open during the peak time in the morning from $6$:$00$ AM to $10$:$00$ AM$.$ During this morning rush hour, the arrival rate to the toll booths is $3,600$ vehicles per hour, and the MTA estimates that the average number of vehicles waiting at any point of time is near the target maximum of $20$ vehicles. What quality of service is being delivered in terms of average waiting time per vehicle during the peak hour?

$2$