A design engineer wants to construct a mean chart for controlling the diameter for a component used in surgeries. The following table contains measurements (in millimeters) of the diameter for a component. Four samples of five units each were taken at random two-hour intervals. What are the X-bar chart upper and lower control limits? Measurement Sample (in millimeters) 1 8 9 10 9 8 2 9 7 9 9 8 3 8 9 9 10 10 4 9 9 9 9 9 Select one: a. 9.872 and 7.828 b. 9.945 and 7.775 O c. 10.01 and 7.15 O d. 9.67 and 7.93 O e. 9.72 and 7.98