For the bookstore sales data in Exercise 1, the correlation of number of sales people and sales is 0.965.

a) If the number of people working is 2 standard deviations above the mean, how many standard deviations above or below the mean do you expect sales to be?

b) What value of sales does that correspond to?

c) If the number of people working is 1 standard deviation below the mean, how many standard deviations above or below the mean do you expect sales to be?

d) What value of sales does that correspond to?