1.) 25 Pittsburgh residents were asked how much sleep they getper night. The mean was 7.2 hours and the standard deviation was0.78 hours. Construct and interpret a 90% confidence interval forthe true mean number of hours of sleep that Pittsburgh residentsget per night.
2.) A sample of 11 Chevy Volt drivers resulted in them having amean of 42.6 miles per gallon (mpg) and a standard deviation of 4.8mpg. Construct and interpret a 95% confidence interval for the meangas mileage of all Chevy Volt drivers.
3.) A researcher believes the mean price of regular gas inPennsylvania has increased from last month's mean of $2.88. Asample of 50 gas stations yields a mean price of $2.98 and astandard deviation of $0.50. Conduct a hypothesis test at the 10%significance level.  Make sure to give thehypotheses, test statistic, p-value, decision, and a practicalinterpretation.
