1. As part of a study of the effect of Facebook on people's happiness, study participants were asked after the study how much, if at all, they planned on changing their Facebook use. The average participant said they planned on reducing their Facebook use by 22%, with a standard deviation of 28%. (Some participants said they planned on increasing their Facebook use.) The sample size was 1637.

A. Give a 95% confidence interval for the population mean.

B. Explain as clearly as you can what your answer to 3a means.