Question 1 The natural variability of the process is measured by a. Sample mean b. Process mean c. Sample standard deviation d. Process standard deviation > Question 2 The average value of the quality characteristic corresponding to in-control state is represented by a. Lower Control Limit (LCL) b. Center Line (CL) c. Upper Control Line (UCL) d. Sample number in the control charts. Question 3 The highest value that a quality characteristic can take before the process becomes out-of-control is called a. Center line b. Upper control limit c. Lower control limit d. Control limit