3. Suppose that you are working for a watch company studying theaverage wrist sizes of people in the population of the UnitedStates.
(a) If you are told that we know from previous studies that thestandard deviation in women’s wrist sizes is 0.5 inches, and from arandom sample of 20 women, the sample mean wrist size was 7.2inches, create a 95% confidence interval for the true mean wristsize.
(b) Your boss comes back and tells you that they found out thatthe sample actually had 30 women, but everything else was correct.Create a new 95% confidence interval based on this information.
(c) Your boss comes back and tells you that they made a mistakeand the 0.5 inch standard deviation was actually just the samplestandard deviation and we don’t know the true value. In addition,it turns out there were only 10 women in the study. After calmingdown, create a new 95% confidence interval based on thisinformation.
