A clinical trial was conducted to test the effectiveness of a drug for treating insomnia in older subjects. Before​ treatment, 19 subjects had a mean wake time of 101.0min. After treatment, the 19 subjects had a mean wake time of 72.4 min and a standard deviation of 21.8 min. Assume that the 19 sample values appear to be from a normally distributed population and construct a 99​% 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 101.0min before the​ treatment? Does the drug appear to be​ effective?