Mid-Valley Travel Agency (MVTA) has offices in 12 cities. The company believes that its monthly airline bookings are related to the mean income in those cities and has collected the following data:

Location	Bookings	Income		Location	Bookings	Income
1	1,098	43,299		7	855	27,482
2	1,131	45,021		8	1,054	33,025
3	1,120	40,290		9	1,081	34,687
4	1,142	41,893		10	982	28,725
5	971	30,620		11	1,098	37,892
6	1,403	48,105		12	1,387	46,198

a). Develop a linear regression model of monthly airline bookings as a function of income.

b). Use the process described in the chapter to evaluate your results.

c). Make the point and approximate 95 percent confidence interval estimates of monthly airline bookings for another city in which MVTA is considering opening a branch, given that income in that city is $39,020.