Clayton Kershaw of the Los Angeles Dodgers is one of the premier pitchers in baseball. His most popular pitch is a four-seam fastball. The data in the next column represent the pitch speed (in miles per hour) for a random sample of 18 of his four-seam fastball pitches.

(a) Is "pitch speed" a quantitative or qualitative variable? Why is it important to know this when determining the type of confidence interval you may construct?
(b) Draw a normal probability plot to verify that "pitch speed" could come from a population that is normally distributed.
(c) Draw a boxplot to verify the data set has no outliers.
(d) Are the requirements for constructing a confidence interval for the mean pitch speed of a Clayton Kershaw four-seam fastball satisfied?
(e) Construct and interpret a 95% confidence interval for the mean pitch speed of a Clayton Kershaw four-seam fastball.
(f) Do you believe that a 95% confidence interval for the mean pitch speed of all major league pitchers' four-seam fastball would be narrower or wider? Why?

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93.63 93.83 94.18 94.15 94.71 95.52 95.07 95.12 95.35 94.62 96.08 93.86 94.75 94.70 95.28 95.49 95.77 93.34