S6B-4. Can someone show me how to do this problem?

Will rate a thumb up for good response thanks so much (PLEASE CIRCLE OR HIGHLIGHT final answer thx)

Linda Boardman, Inc., an equipment manufacturer in Boston, has submitted a sample cutoff valve to improve your manufacturing process. Your process engineering department has conducted experiments and found that the valve has a mean (u) of 12.00 and a standard deviation (6) of 0.06. Your desired performance is u = 12.00 = 3 standard deviations, where o = 0.050. For the given information, the process capability index (Cpk) = (round your response to three decimal places)