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: Click the icon to view the table of factors for calculating three-sigma limits for the x-chart and R-chart. 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 LCL= seconds and all of the sample means are between UCL=seconds and LCLX= seconds, the call center access time is in statistical control (Enter your responses rounded to two decimal places.)