The postmaster of a small western town receives a certain number of complaints each day about mail delivery. 1 2 Number of complaints 4 11 15 355 4 48 59 75 66 DAY 8 8 10. 11 96 12 13 4 14 2 10 97 93 14 13 Click here for the Excel Data File a. Determine three-sigma control limits using the above data. (Round your intermediate calculations to 4 decimal places and final answers to 3 decimal places. Leave no cells blank - be certain to enter "O" wherever required. Round up any negative control limit value to zero.) UCL LCL b. Is the process in control? O Yes