TABLE 14-5
a Microeconomist Wants to Determine How Corporate Sales

TABLE 14-5
A microeconomist wants to determine how corporate sales are influenced by capital and wage spending by companies. She
proceeds to randomly select 26 large corporations and record information in millions of dollars. The Microsoft Excel output
below shows results of this multiple regression
$$\begin{array}{l}\text { Regression Statistics }\\\begin{array} { l r } \hline \text { Multiple R } & 0.830 \\\text { R Square } & 0.689 \\\text { Adjusted R Square } & 0.662 \\\text { Standard Error } & 17501.643 \\\text { Observations } & 26\end{array}\end{array}$$

ANOVA
$\begin{array}{lcrrrr}\hline & \text { d f }&\text { S S } & \text { M S } & \text { F }&\text { Significance F } \\\hline \text {Regression} & 2 & 15579777040 & 7789888520 & 25.432 & 0.0001 \\\text {Residual }& 23 & 7045072780 & 306307512 & & \\\text {Total }& 25 & 22624849820 & & & \\\hline\end{array}$

$$\begin{array} { l c c c c } & \text { Coefficients } & \text { Standard Error} & \text { t Stat } & \text { p-value } \\\text { Intercept } & 15800.0000 & 6038.2999 & 2.617 & 0.0154 \\\text { C apital } & 0.1245 & 0.2045 & 0.609 & 0.5485 \\\text { W ages } & 7.0762 & 1.4729 & 4.804 & 0.0001 \\\hline\end{array}$$

-Referring to Table 14-5, when the microeconomist used a simple linear regression model with sales as the dependent variable and wages as the independent variable, she obtained an r² value of 0.601. What additional percentage of the total variation of sales has been explained by including capital spending in the multiple regression?

A) 22.9%
B) 31.1%
C) 60.1%
D) 8.8%