A quality analyst wants to construct a sample mean chart for controlling a packaging process. He knows from past experience that the process standard deviation is two ounces. Each day last week, he randomly selected four packages and weighed each. The data from that activity appears below. (a) Calculate upper and lower control limits for both sample means and ranges. (b) Is this process in control? Explain--a simple Yes or No is insufficient. (c) What additional steps should the quality assurance team take?