Question: A critical dimension of the service quality of a call center is the wait time of a caller to get to a sales representative. Periodically, random samples of three customer calls are measured for time. The results of the last four samples are in the following table: Time (sec) Sample 1 2 3 1 501 490 488 2 509 498 487 3 503 492 496 4 497 507 487 Click the icon to view the table of factors for calculating three-sigma limits for the x- -chart and R-chart. Factors for calculating three-sigma limits for the x-- chart and R-chart Size of Sample(n) Factor for UCL and LCL for x-chart (A2) Factor for LCL forR-Chart (D3) Factor for UCL forR-Chart (D4) 2 1.888 0 3.267 3 1.023 0 2.575 4 0.729 0 2.282 5 0.577 0 2.115 6 0.483 0 2.004 7 0.419 0.076 1.924 8 0.373 0.136 1.864 9 0.337 0.184 1.816 10 0.308 0.223 1.777 a. Assuming that management is willing to use three-sigma control limits, and using only the historical information contained in the four samples, show that the call center access time is in statistical control. Since all the sample ranges are between UCLr =( )seconds and LCLr =( )seconds and all of the sample means are between UCL -x = ( ) seconds and LCL x- = ( ) seconds, the call center access time is in statistical control. (Enter your responses rounded to two decimal places.)