A clinical trial was conducted to test the effectiveness of a drug for treating insomnia in older subjects. Before treatment, 20 subjects had a mean wake time of 105.0 min. After treatment, the 20 subjects had a mean wake time of 81.7 min and a standard deviation of 22.5 min. Assume that the 20 sample values appear to be from a normally distributed population and construct a 90% confidence interval estimate of the mean wake time for a population with drug treatments. What does the result suggest about the mean wake time of 105.0 min before the treatment? Does the drug appear to be effective? Construct the 90% confidence interval estimate of the mean wake time for a population with the treatment. Omin < u