In a fabric manufacturing factory, the quality control process using control charts from SPC. In an hour there are a total of 5 samples are taken each having 4 observations regarding the thickness of fabric in measured in millimeters. In a particular hour, the sample means bar)are noted to be: 156.46, 199.62, 189.31, 102 22 and 112.09 respectively. In the same sample, the corresponding ranges are: 11.97. 12.17.13.94.11.36 and 11.83 respectively. What are the lower and upper control limits for the X-bar chart? O a 145.40, 190.72 Ob 143.55.165.47 Oc. 142.92.160.96 Od 156.55.170.47 O e 144.77.159.11 Ot None is correct GE NEXT PAGE