4. PC World rated four component characteristics for 10 ultraportable laptop computers: features; performance; design; and price. Each characteristic was rated using a 0-100 point scale. An overall rating, referred to as the PCW World Rating, was then developed for each laptop. The following tables show regression output examing relationships between the performance rating, features rating, and the PCW World Rating for the 10 laptop computers (PC World website, February 5, 2009).                                                                               Regression Statistics                       Multiple R 0.743236929                       R Square 0.552401133                       Adjusted R Square 0.496451275                       Standard Error 2.59221488                       Observations 10                                                 ANOVA                           df SS MS F Significance F               Regression 1 66.34338 66.34338 9.873146 0.013760372               Residual 8 53.75662 6.719578                   Total 9 120.1                                                 Coefficients Standard Error t Stat P-value Lower 95%               Intercept 66.0623015 3.793359 17.41525 1.21E-07 57.31479965               Performance 0.169893409 0.054069 3.142156 0.01376 0.045209954                                         SUMMARY OUTPUT                                                 Regression Statistics                       Multiple R 0.914818939                       R Square 0.836893692                       Adjusted R Square 0.790291889                       Standard Error 1.67285332                       Observations 10                                                 ANOVA                           df SS MS F Significance F               Regression 2 100.5109324 50.2554662 17.9584 0.001752               Residual 7 19.58906762 2.79843823                   Total 9 120.1                                                 Coefficients Standard Error t Stat P-value Lower 95%               Intercept 39.98196819 7.855064392 5.08996059 0.001415 21.40769               Performance 0.113382175 0.038458631 2.94815937 0.021463 0.022442               Features 0.382032562 0.109333005 3.49421076 0.010071 0.123501                                         4a. Determine the estimated regression equation that can be used to predict the PCW World Rating using the performance rating as the independent variable.     ŷ = 66.062 + 0.170 x_1               Correct                         4b. Determine the estimated regression equation that can be used to predict the PCW World Rating using both the performance rating and the features rating     ŷ = 39.982 + 0.113 x_1  + 0.382033 x_2         Check carefully                         4c. Predict the PCW World Rating for a laptop computer that has a performance rating of 80 and a features rating of 70.