The accompanying data file contains 35 observations for an ice cream truck driver's daily income (Income in $), number of hours on the road (Hours), whether it was a particularly hot day (Hot 1 if the high temperature was above 85F, 0 otherwise), and whether it was a Holiday (Holiday 1, 0 otherwise). Consider two models where Model 1 predicts Income on the basis of Hours, Hot, and Holiday and Model 2 also includes the interaction between Hot and Holiday. Click here for the Excel Data File a-1. Use the holdout method to compare the predictability of the models using the first 24 observations for training and the remaining 11 observations for validation. Report the estimates of Models 1 and 2 derived from the training set. Note: Negative values should be indicated by a minus sign. Round your answers to 2 decimal places. Predictor Variable Constant Hours Hot Holiday Hot Holiday Model 1) Model 2 a-2. Calculate the RMSE of the two models in the validation set. Note: Do not round intermediate calculations and round your final answers to 2 decimal places. Model 1 Model 2 RMSE