Refer to Table 56.1 - Factors for Computing Control Chart Limits (3 sigma) for this problem. Auto pistons at Wemming Chung's plant in Shanghai are produced in a forging process, and the diameter is a critical factor that must be controlled. From sample sizes of 10 pistons produced each day, the mean and the range of this diameter have been as follows: Day 1 2 Mean x (mm) 156.9 151.2 151.6 153.5 154.6 Range R (mm) 4.4 4.8 3.9 5.2 4.5 3 4 5 a) What is the value of ? = x= 153.56 mm (round your response to two decimal places). b) What is the value of R? R= = 4.56 mm (round your response to two decimal places). c) What are the UCL; and LCL; using 3-sigma? Upper Control Limit (UCL) = mm (round your response to two decimal places)