$39$ customers arrive per hour $($ca $=0\mathrm{.}84)$ during lunch and join a single line which is served by $6$ clerks. It takes about $7$ minutes to serve each customer $($cp $=0\mathrm{.}30).$

How long does the average customer wait in line $($in minutes$)?$

Group of answer choices

A: $0\mathrm{.}90$

B: $1\mathrm{.}93$

C: $0\mathrm{.}95$

D: $0\mathrm{.}98$