Question: Consider a multiple regression of Y (gas mileage) on two predictor variables (vehicle weight) and (engine type). Suppose is an indicator variable that takes the value +1, if the engine is fueled by gasoline and 0, if the engine is fueled diesel. Is there some numeric value for variable such that if is less than this value the mean fuel economy for gasoline vehicles will be lower than the mean fuel economy of the diesel vehicles, but if is greater than this value, the mean fuel economy for gasoline vehicles will be higher than the mean fuel economy of the diesel vehicles