Time Miles Weight Speed Oil 7.8 42.8 18 42 The maintenance manager at a trucking company wants to build a regression model to forecast the time (in years) until the first engine overhaul based on four predictor variables: (1) annual miles driven (in 1,000s of milles). (2) average load weight (in tons). (3) average driving speed (in mph), and (4) oll change interval (in 1,000s of miles). Based on driver logs and onboard computers, data have been obtained for a sample of 25 trucks. A portion of the data is shown in the accompanying table. 10 0.8 98.6 21 45 34 8.2 43.1 16 64 10 1.5 110.3 27 56 28 11 101.9 30 50 19 Time Miles Load Speed oil 23 97.3 25 62 16 7.8 42.8 18.0 42.0 10.0 0.8 98.6 21.0 45.0 34.0 2.7 93 22 56 10 7.6 53.8 15 67 13 6.0 60.7 27.0 58.0 17.0 7.9 51.4 21 50 17 Click here for the Excel Data File 4.3 85 21 51 24 0.6 120.2 26 47 26 b. Estimate the regression model. (Negative values should be indicated by a minus sign. Round your answers to 4 decimal places.) 5.1 77.6 28 46 27 5.1 68.9 17 48 24 Predicted Time= Miles Load Speed+ Oil 5.5 54.9 24 58 23 5.8 67.2 22 54 22 8.8 39.7 24 47 18 d. What is the predicted time before the first engine overhaul for a particular truck driven 60,000 miles per year with an average load of 25 tons, an average driving speed of 59 mph, and 17,000 miles between oil changes. (Do not round intermediate calculations. Round final answer to 2 decimal places.) 5.6 5.6 4.6 6.2 Predicted Time years 66621 52.5 17 59 29 53.7 15 51 18 74.8 19 70 20 58.2 16 55 16 6.7 52.5 19 56 24 7.1 68.5 19 54 24 11/1/1 3.8 94.3 24 59 25 6.9 45.6 21 55 11 6.0 60.7 27 58 17