Aclinical trial was conducted to test the effectiveness of a drug used for treating insomnia in older subjects. after treatment with the drug, 1313 subjects had a mean wake time of 96.996.9 min and a standard deviation of 42.442.4 min. assume that the 1313 sample values appear to be from a normally distributed population and construct a 9595% confidence interval estimate of the standard deviation of the wake times for a population with the drug treatments. does the result indicate whether the treatment is effective?