Chapter 2.3, Problem 21E

(a)

To determine

To calculate: The least square regression line with $x=1$ corresponding to first quarter of $2015$ that model the provided data:

Quarter	$1$	$2$	$3$	$4$	$5$	$6$	$7$	$8$
Revenue	$47.4$	$48.9$	$49.8$	$49.3$	$49.8$	$49.8$	$49.6$	$50.4$

(b)

To determine

To calculate: The revenue in the second quarter of $2017$ by using the obtained model that fit the provided data:

Quarter	$1$	$2$	$3$	$4$	$5$	$6$	$7$	$8$
Revenue	$47.4$	$48.9$	$49.8$	$49.3$	$49.8$	$49.8$	$49.6$	$50.4$

(c)

To determine

To calculate: The first full quarter when the revenue exceeds $\$52$ billion by using the obtained model that fit the provided data.

(d)

To determine

To calculate: The correlation coefficient for the provided data:

Quarter	$1$	$2$	$3$	$4$	$5$	$6$	$7$	$8$
Revenue	$47.4$	$48.9$	$49.8$	$49.3$	$49.8$	$49.8$	$49.6$	$50.4$