Estimating a Population Mean A clinical trial was conducted to test the effectiveness of the drug zopiclone for treating insomnia in older subjects. Before treatment with zopiclone, 36 subjects had a mean wake time of 101.5 minutes. After treatment with zopiclone, the 36 subjects had a mean wake time of 97.5 minutes and a standard deviation of 40.25 minutes. Assuming that wake time is normally distributed, construct a 95% confidence interval estimate of the mean wake time for a population with zopiclone treatments. What does the interval suggest about the mean wake time of 101.5 minutes before the treatment? Does zopiclone appear to be effective?