Joe's Sporting Goods wants to forecast quarterly sales figures using a quadratic trend model. The store has collected 12 quarters of data and needs your help to analyze the data. The relevant regression output is in the following table.

Regression Statistics
	Coefficients
Intercept	263.4545
X Variable 1	5.985514
X Variable 2	4.922577

	A	B	C	D	E	F
1			Time		Actual	Quadratic
2	Year	Qtr	Period	Time^2	Sales	Trend
3	1	1	1	1	284
4		2	2	4	184	295.1
5		3	3	9	365	325.7
6		4	4	16	492	366.2
7	2	1	5	25	485	416.4
8		2	6	36	277	476.6
9		3	7	49	606	546.6
10		4	8	64	722	626.4
11	3	1	9	81	763	716.1
12		2	10	100	593	815.6
13		3	11	121	912	924.9
14		4	12	144	1145	1044.1

How is a quadratic term added to the problem if we want to develop a quadratic trend model?