In order to determine whether or not the sales volume of a company (Y in millions of dollars) is related to advertising expenditures (X1 in millions of dollars) and the number of salespeople (X2), data were gathered for 10 years. Part of the regression results is shown below.

Coefficients Standard Error

Intercept 7.0174 1.8972

X1 8.6233 2.3968

X2 0.0858 0.1845

ANOVA

DF SS MS F

Regression 321.11

Residual (Error) 63.39

a. Use the above results and write the regression equation that can be used to predict sales. 

b. Estimate the sales volume for an advertising expenditure of 3.5 million dollars and 45 salespeople. Give your answer in dollars.

c. At a = 0.05, test to determine if the fitted equation developed in Part a represents a significant relationship between the independent variables and the dependent variable. (What is the F score?) 

d. At a = 0.05, test to see if b1 is significantly different from zero. 

e. Determine the multiple coefficient of determination. 

f. Compute the adjusted coefficient of determination.