Use R Studio, library(MPV) data("table.b1") for this problem

Consider the football data in Table B.1, found within Appendix B of the textbook. Construct the overdetermined matrix equation for the multiple linear regression. What are the sizes of each matrix? Fit a multiple linear regression model relating the number of games won to the team's passing yardage (x2), the percentage of rushing plays (x7), and the opponents' yards rushing (x8). Which variable explains the most variance in the dependent variable?

If two variables are correlated, does the variance explained by both variables separately add to the variance explained by the model at large? What situations could arise in practical work where this might be an issue?