The amount of carbon dioxide absorbed by a jogger follows a Normal distribution, with a mean of 20 kg/hour and standard deviation of 6.8 kg/hour.

If 40 joggers are randomly selected, what is the probability that the average amount of carbon dioxide absorbed by these joggers is less than 22.4 kg/hour?

Answer parts (a) through (f) below. No units of measure are required for any answer.

(a) State the sample size.

(b) State the mean of the sampling distribution.

(c) Calculate the standard deviation of the sampling distribution. Hint: 6.8 is not the correct answer. Provide your answer rounded to 2 decimal places.

(d) Calculate the z-score. Provide your answer rounded to 2 decimal places.?