Fifteen mid-western and mountain states have united in an effort to promote and forecast tourism. One aspect of their work has been related to the dollar amount spent per year on domestic travel (DTE) in each state. They have the following estimates for disposable personal income per capita (DPI) and DTE:

State	DPI	DTE ($Millions)
Minnesota	$17,907	$4,933
Iowa	15,782	1,766
Missouri	17,158	4,692
North Dakota	15,688	628
South Dakota	15,981	551
Nebraska	17,416	1,250
Kansas	17,635	1,729
Montana	15,128	725
Idaho	15,974	934
Wyoming	17,504	778
Colorado	18,628	4,628
New Mexico	14,587	1,724
Arizona	15,921	3,836
Utah	14,066	1,757
Nevada	19,781	6,455

a. From these data, estimate a bivariate linear regression equation for domestic travel expenditures (DTE) as a function of disposable income per capita (DPI):

b. Illinois, a bordering state, has asked that this model be used to forecast DTE for Illinois under the assumption that DPI will be $19,648.

c. Given that actual DTE turned out to be $7,754 (million), calculate the percentage error in your forecast.