Consider a single production line made up of $5$ workstations, each with a single machine and processing time of $15$ secs$.$ What is the bottle neck rate, in parts$/$sec$?$

Group of answer choices

$6\mathrm{.}66$

$0\mathrm{.}067$

$0\mathrm{.}0833$

$0\mathrm{.}166$