1, the estimated change in mean salary (in thousands of dollars) as a result of spending an extra hour per day studying is? 2,interpret the 95% confidence interval for B13,Approximately____% of the total variation in starting salary can be explained by the numbers of hours spent studying per day

It is believed that, the average numbers of hours spent studying per day (HOURS) during undergraduate education should have a positive linear relationship with the starting salary (SALARY, measured in thousands of dollars per month) after graduation. Given below is the Excel output for predicting starting salary (1) using number of hours spent studying per day (X) for a sample of 51 students. NOTE: Only partial output is shown Regression Statistics Multiple R 0.8857 R Square 0.7845 Adjusted R Square 0.7801 Standard Error 1.3704 Observations 51 ANOVA SS AS F Significance F Regression 1 335.0472 335.0473 178.3859 Residual 1.8782 Total 50 427.0798 Standard Coefficients Error f Stat P-value Lower 0596 Upper 95%% Intercept -1.8940 0.4018 47134 0.0000 -2.7015 1.0865 Hours 0.9795 0.0733 13.3561 0.0000 0.8321 1.1269 Note: 2.051E - 05 = 2.051 * 10-05 and 5.944E - 18 =5.944 - 10-18