Cars arrive at a local JLUBE franchise at the rate of $1$ every $12$ minutes. Service times are exactly $15$ minutes. Jack Burns, the JLUBE owner, has decided to open a second work bay, i$.$e$.,$ make the shop into a two$-$channel system. Under this new scheme, the average customer will wait in an $\_\_\_\_\_\_\_\_$ line

M$/$M$/1$

M$/$M$/2$

M$/$D$/2$

M$/$D$/1$

M$/$G$/2$