The following table contains the data for a sample size of nequals6 taken during the past 3 hours: Sample 1 2 3 4 5 6 7 8 9 10 x overbar 51 53 48 51 51 54 57 R4735457 a) What are the x overbar-chart control limits when the machine is working properly? Calculate the upper control limit of the x overbar-chart Calculate the lower control limit of the x overbar-chart. What are the R-chart control limits when the machine is working properly? Calculate the upper control limit of the R-chart. Calculate the lower control limit of the R-chart. The process is in control if all sample mean and range values are within the control limits. What seems to be happening? Has the process been in control? Yes or no?