QUESTION 11 Control chart for X and Rars to be established on a certain dimension part, measured in millimeters. Data were collected in subgroup sizes of 6 and are given in Table QUI. Table Oil : Data Subgroup No. 1 2 3 4 5 6 7 8 9 JO 11 12 x 20.35 20.40 20.38 20.65 20.20 20.40 20.43 20.37 20.48 20.42 20.39 20.40 R 0.34 0.36 0.32 0.36 0.36 0.35 0.31 0.34 0.30 0.37 0.29 0.30 Subgroup No. 13 14 15 16 17 18 19 20 21 22 23 24 X 20.45 20.32 20.48 20.50 20.32 20.37 20.44 20.40 20.41 20.39 20.43 20.46 R 0.36 0.34 0.36 0.37 0.59 0.45 0.38 0.33 0.80 0.34 0.51 0.30 (a) Determine the central line and control limits. [5 marks) 6) Determine the process capability to tight specification 20.4+0.20 mm. [3 marks] The process is improved and produces a new standard deviation (a1= 0.05), determine the new capability index. [3 marks] (d) Determine the Cpk when process is improved and produces a new standard deviation (a1=0.05). [3 marks) If the customer change the tolerancel= 0.15), determine the new Cpk and discuss the action to be taken. [6 marks)