Develop a multiple-regression model for auto sales as a function of population and household income from the following data for 10 metropolitan areas:

a. Estimate values for bt). b, and h: for the following model:
AS = b0 + b1(INC) + b2(POP)
b. Arc the signs you find for the coefficients consistent with your expectations? Explain.
c. Arc the coefficients for the two explanatory variables significantly different from zero? Explain.
d. What percentage of the variation in AS is explained by this model?
e. What point estimate of AS would you make for a city where INC = $23,175 and POP = 128.07? What would the approximate 95 percent confidence interval be?

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Auto Sales (AS) ($000) $185,792 85,643 97,101 100,249 527,817 403,916 78,283 188,756 29,531 91,944 Household Income (INC) (So00) Population Area POP) (000) 23,409 19,215 20,374 16,107 23,432 19,426 18,742 18,553 21,953 16,358 133.17 110.86 68.04 99.59 289.52 339.98 89.53 55.78 248.95 102.13 6 9 10