A three-variable regression gave the following results: (12 marks) Source of variation Sum of squares (SS) d.f. MSS Due to regression (ESS) 65,965 Due to residual (RSS) Total 66,042 14 1. Fill in the missing cells 2. Find R 3. Find adjusted R² 4. Test the hypothesis that X2 and X3 have zero impact on Y 5. Which test do you use and why? 6. From the preceding information, can you determine the individual contribution of X2 and X3 toward Y and why?