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QB.2: The data in the table below are collected for the waiting time in a call center. The call center supervisor is suspecting that there was a small shift in the waiting time in the last month, where the target value is 160 sec. Set up an EWMA control chart for monitoring the waiting time using 1=0.1, L=2.7, and o=2.9 sec. (show the UCL and LCL for each sample) Does the waiting time seem to be in statistical control? Waiting Waiting Sample No time (sec.) Sample No time (sec.) 1 153 11 152 169 12 149 13 159 14 159 15 166 16 167 149 17 165 160 18 158 158 163 169 2 157 163 3 169 sta 158 6 7 8 9 10 19 20 146