A manager wishes to build a control chart for a process. A total of five (05) samples are collected with seven (07) observations within each sample. The sample means (X-bar) are; 15.36 14.61,16.36,20.28, and 15.77 respectively. Also, the corresponding ranges are; 10.79.8.37, 2.81,8.17, and 3.31 respectively. The lower and upper control limits of the R-chart are respectively Select one: O a. 0, 14.11 O b. O, 15.25 c. None is correct d. 0,13.38 e. 0.54, 12.84