Breann can handle about nine customers per hour at her one$-$person comic book store. The customer arrival rate averages about six customers per hour. Breann is interested in knowing the operating characteristics of her single$-$channel, single$-$phase queuing system. Do not round intermediate calculations. Round your answers to three decimal places.

$=$

$=$

$=$

customer$($s$)$

$=$

customer$($s$)$

$=$

hours

$=$

hours

How would Breann's queuing system operating characteristics change if she added another cashier and increased her service rate to eighteen customers per hour? Do not round intermediate calculations. Round your answers to three decimal places.

$=$

$=$

$=$

customer$($s$)$

$=$

customer$($s$)$

$=$

hours

$=$

hours