A multiple least squares regression was carried out using a sample of 27 observations. From the sample data, the following partial outputs were obtained: SST = ̑(yi - ȳ)" = 288.69, SSE = ̑ei" = ̑(yi - ŷ)" = 155.86. Coefficients: Predictor Coef SE Coef T Constant 13.187 10.871 1.213 x1 9.37 5.177 1.810 x2 -9.005 3.653 -2.465 x3 -3.286 1.698 -1.935 x4 17.449 12.718 1.372 Answer the following: a) The 96% confidence interval for ̒1 is: b) One of the data points had x1 = 3.75, x2 = 5.1, x3 = 3.45, x4 = 3.25, and y = 47.32155. Find the predicted value and the residual corresponding to this observation. The predicted value ŷ: The residual: