Data from a small bookstore are shown in the accompanying table. The correlation for the data is 0.972. Complete parts a through d. 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?