In painting an automobile at the factory, the thickness of the color coat has a process me...

In painting an automobile at the factory, the thickness of the color coat has a process mean of 1.00mil and a process standard deviation of 0.07mil. Twenty samples of five cars were tested, resulting in the mean paint thicknesses shown below. (a)Construct upper and lower control limits for the  chart, using the given process parameters. (b) Plot the data on the control chart. (c) Is this process in control? Explain your reasoning.