I NEED TO FIND THE ANSWER TO THIS QUESTION.

With a height of 62 in, Johnson was the shortest president of a particular club in the past century. The club presidents of the past century have a mean height of 71.4 in and a standard deviation of 2.8 in.

a. What is the positive difference between Johnson's height and the mean?

b. How many standard deviations is that [the difference found in part (a)]?

c. Convert Johnson's height to a z score.

d. If we consider "usual" heights to be those that convert to z scores between −2 and 2, is Johnson's height usual or unusual?

The positive difference between Johnson's height and the mean is ? in.