Tool life (or how long it takes for a tool to wear out) is important in manufacturing. An engineer did a study to see how two factors, rotational speed and vertical pressure, affected the tool life of a drill. Tool life is in hours of operation, speed is in revolutions per minute, and pressure is in pounds of force.The data and analysis are shown below.

speed pressure tool life 330 10 55 Regression Statistics 630 10 40 Multiple R 0.919 330 20 51 R Square 0.845 630 20 35 Adjusted R Square 0.807 330 10 53 Standard Error 3.540 630 10 36 Observations 11 330 20 44 630 20 30 ANOVA 480 14 40 SS MS F Signf F 480 14 47 Regression 2 548.312 274.156 21.881 0.000571 480 14 38 Residual 8 100.234 12.5292 Total 10 648.545 Coeff Stand Err t Stat Pvalue Lower 95% Upper 95% Intercept 75.965 5.533 13.729 0.000 63.206 88.725 speed -0.052 0.008 -6.193 0.000 -0.071 -0.032 pressure -0.579 0.249 -2.326 0.048 -1.153 -0.005Regression Statistics Multiple R 0.932 R Square 0.868 Adjusted R Square 0.856 Standard Error 416.909 Observations 36 ANOVA SS MS F Signif F Regression 3 36594809 12198270 70.180391 3.64354E-14 Residual 32 5562018.5 173813.08 Total 35 42156828 Coeff Stand Err t Stat P_value Lower 95% Upper 95% Intercept 3356.887 6928.042 0.485 0.631 -10755.061 17468.835 Month 91.684 37.523 2.443 0.020 15.253 168.116 Customers 6.088 70.895 0.086 0.932 -138.321 150.496 HOT 332.236 175.818 1.890 0.068 -25.893 690.365Coeff Stand Err t Stat P_value Intercept 3356.887 6928.042 0.485 0.631 Coeff Stand Err t Stat P_value Month 91.684 37.523 2.443 0.020 Intercept 3951.662 142.835 27.666 0.000 Customers 6.088 70.895 0.086 0.932 Month 94.854 6.610 14.349 0.000 HOT 332.236 175.818 1.890 0.068 HOT 338.297 158.589 2.133 0.040 Coeff Stand Err t Stat Pvalue Coeff Stand Err t Stat Pvalue Intercept -1845.743 6600.474 -0.280 0.782 Intercept -13241.714 1459.105 -9.075 0.000 Month 64.647 36.014 1.795 0.082 Customers 176.520 13.603 12.976 0.000 Customers 59.868 67.414 0.888 0.381 HOT 168.427 174.345 0.966 0.341Month Milk Price Forecast Error 2.30 2.38 2.31