For the question about e-mail in the previous exercise, the 14 females in the GSS of age at least 80 had the responses 0, 0, 0, 0, 1, 1, 1, 2, 2, 6, 6, 7, 7, 10.
a. Using the web app, software or a calculator, find the sample mean and standard deviation and the standard error of the sample mean.
b. Find and interpret a 90% confidence interval for the population mean.
c. Explain why the population distribution may be skewed right. If this is the case, is the interval you obtained in part b useless, or is it still valid? Explain.