A$$ single$-$server service facility had the capacity to serve $38$ customers per hour on average. The average customer demand was $31$ customers per hour.

Determine the average waiting time in the line in minutes.

Part $2$

A$.$

$3\mathrm{.}88$

B$.$

$6\mathrm{.}99$

C$.$

$5\mathrm{.}09$

D$.$

$3\mathrm{.}04$