Calculate confidence intervals for both a and b a) Julia has been jogging over a period of several years. The standard deviation of her times to run 2 miles is o = 1.80. A random sample of 90 of her...

Extracted text: Calculate confidence intervals for both a and b a) Julia has been jogging over a period of several years. The standard deviation of her times to run 2 miles is o = 1.80. A random sample of 90 of her jogging times over the last year gives a sample mean of 15.60 minutes. Find a 95% confidence interval for u and interpret your answer a) A random sample of 188 books purchased at a local bookstore showed that 66 of the books were murder mysteries. Find a 90% confidence interval for the proportion of books sold by this store that are murder mysteries.