10 points An article in the National Geographic News (U.S. Racking Up Huge Sleep Debt." February 24, 2005) argues that Americans are increasingly skimping on their sleep. A researcher in a small Michwestern town wants to estimate the mean weekdaysleep time of its adult residents. He takes a random sample of 80 adult residents and records their weekday mean sleep time as 6.4 hours. Assume that the population standard deviation is fairly stable at 1.8 hours. [You may find it useful to reference the table.) a. Calculate the 95% confidence interval for the population mean weekdaysleep time of all adult residents of this Midwestern town (Round Intermediate calculations to at least 4 decimal places. Round " value to 2 decimal places and final answers to 2 decimal places.) blood Confidence interval ta Book Print Reference b. Can we conclude with 95% confidence that the mean sleep time of al adult residents in this midwestern town is not 7 hours? Yes. Since the confidence interval contains the value 2 Yes. Since the confidence interval does not contain the value 7 No, since the confidence interval contains the value No, since the confidence interval does not contain the value 7