For the following bookstore sales data, the correlation is 0.965.

Number of Salespeople Working               Sales (in $1000)
2................................................................................................10
3................................................................................................11
7................................................................................................13
9................................................................................................14
10..............................................................................................18
10..............................................................................................20
12..............................................................................................20
15..............................................................................................22
16..............................................................................................22
20..............................................................................................26
x = 10.4............................................................................ŷ = 17.6

SD(x) = 5.64...............................................................SD(y) = 5.34

a) If the number of people working is two 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 one 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?