A production line is to be designed for a job with four workstations. The actual duration on each of the workstations are $2\mathrm{.}4$ minutes, $1\mathrm{.}4$ minutes, $0\mathrm{.}9$ minutes, and $1\mathrm{.}7$ minutes, resp. If the theoretical cycle time is $3\mathrm{.}0$min., what is the actual idle time per cycle?

$5\mathrm{.}6$ minutes

$6\mathrm{.}4$ minutes

$4\mathrm{.}8$ minutes

$3\mathrm{.}2$ minutes