The New York City school board wants to estimate the mean size μ of AP statistics classes in New York City high schools. The board obtained the following random sample of AP statistics class sizes:

24 29 29 23 25 24 33 26 24 29 27 26

22 32 24 21 19 29 31 26 29 31 16

Question 1a. Use the data above to construct a 90% confidence interval for the mean class size μ. (calculate y and s to 3 decimal places).

lower bound of confidence interval?
upper bound of confidence interval?

Question 1b. Mark the following statement as true or false: The probability is 0.90 that the mean size μ of high school classes is contained in the interval calculated above.