Answer:
2. is the engine size.
Explanation:
When we make a scatter plot to predict gas mileage from engine size, the explanatory variable on x axis would be the engine size because for predicting any one variable we definitely need one explanatory variable and since we are predicting gas mileage then engine size will be the explanatory variable on x axis.
The equation of regression is:
,
where
= Dependent or predicting variable (Output)
= Independent or Explanatory variable (Input)
= Intercept parameter
= Slope parameter
= error terms