Several complaints recently have been sent to the LA city office regarding the increasing incidence of congestion on the city's streets. The complaints attribute the cause of these traffic tie-ups to a lack of synchronization of the traffic lights. The lights are controlled by a main computer system, and adjusting this program is costly. Therefore, the city is reluctant to change the situation unless a clear need is shown. During the past three months, the office initiated a study and collected 168 data each month at major intersections and identify the # of congestion incidents. The congestion data is shown below. Month Congestion Incidents # 1 4 2 12 3 3 9 What is the upper control limit, for a 4-sigma quality standard, based on the above data? Numbers only, keep 3-decimal if not exact, either round up or down is ok