Leah's Toys guarantees to ship customer orders in 24 hours or less. The following chart contains results for five samples of nine customer orders...

0.04

4. A machine is designed to fill bottles to between 16.01 and 15.98 ounces. Thirty samples of bottles filled by the machine were randomly selected from the process. The sample bottles yielded a mean (mu) of 15.99 and a standard deviation of 0.0025. Calculate the process capability index for the bottle filling machine and comment on its capability.