There are 50 individual observations of pH readings in a chemical reactor during the manufacture of an additive.

Taking moving ranges of 2 by 2 we have a sum of 3.0 in the column of moving ranges.

For that variable the specification limits are 6.7 and 6.9.

For the sample data, a kurtosis equal to 2.18 and a bias equal to 0.63 were calculated.

Calculate Clements' capacity index Cp.

Please specify the answer.