1. Model tting: (a) (9pts each) Fit three regression models to predict the response variable. Ensure that each model includes the main predictor of interest and at least two predictor variables in total. For each model, give the predicted regression equation. Also, include a one-totwo sentence description on why you chose the predictors in your model. (b) (Spts) Determine, using appropriate criteria, the best model for predicting your response variable out of the ones considered in part 1(a). You will use this model to answer questions 2, 3, and 4