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 (X-bar) are noted to be: 156.46, 199.62 189.31, 102.22, and112.09 respectively. In the same sample, the corresponding ranges are: 11.97, 12.17, 13.94, 11.86, and 11.83 respectively. What are the lower and upper control limits for the R chart? a. 0,30.47 b. None is correct c. 0, 31.17 d. 0, 29.17 e. 0,24.71 f. 0,28.17 Clear my choice