For a process with a centered mean to achieve three-sigma quality, how many standard deviations (assuming its value is known or estimated) can be covered between the lower and upper specification limits (LSL and USL)? 1 2 12 6 3 A supplier claims to have a product specification of 5 +0.1 kg in weight. According to its machine operator's record, the production process actually has the sample mean of 5.02 kg and a standard deviation of 0.04 kg. Calculate the process capability index for this supplier. What is your conclusion of the supplier's quality performance? Cpk - 0.67, the process has not even reached a 3-sigma quality Cpk = 1.33, the process has achieved a 6-sigma quality Cpk = 1.33, the process has achieved a 3-sigma quality Cpk - 2, the process has achieved a 6-sigma quality Cpk - 2. the process has achieved a 3-sigma quality