To determine the mean height ? of male students on your campus, you will evaluate an SRS of students. You know from government data that the standard deviation of heights of young men is regarding 2.8 inches. Assume that the distribution of heights of all
a) How large an SRS should you take to decrease the standard deviation of the sample mean to one-half inch?
b) If you choose one student at random, what is the probability that he is between 70 and 72 inches tall? (Use 4 decimal places.)
c) What is the probability that the mean height of your sample is between 70 and 72 inches? (Use 3 decimal places.)