Finding Confidence Intervals. In Exercise assume that each sample is a simple random sample obtained from a population with a normal distribution. Highway Speeds Listed below are speeds (mi/h)...

Finding Confidence Intervals. In Exercise assume that each sample is a simple random sample obtained from a population with a normal distribution.

Highway Speeds Listed below are speeds (mi/h) measured from southbound traffic onI-280 near Cupertino, California (based on data from SigAlert). This simple random sample was obtained at 3:30 p.m. on a weekday. Use the sample data to construct a 95% confidence interval estimate of the population standard deviation. Does the confidence interval describethe standard deviation for all times during the week?