Exhibit 1-1. A multiple linear regression was used to study how family spending (y) is influenced by income (X1), family size (X2), and additions to savings (X3). The variables y, X1, and X3 are measured in thousands of dollars per year. The following results were obtained. ANOVA DF SS Source of variation Regression Residual Total k = 3 n-k-1 = 26 In-1 = SSR= 25 SSE = 85 SST = Standard Error Intercept x 1 Coefficients 7.58 b1 = -2.35 b2 = 2.5 b3 = 0.067 0.6379 0.44 x2 x3 0.33 Refer to Exhibit 1-1. percent of variations in family spending was explained by the estimated regression model is a. 35 Ob.28 O c. 23 O d. 30