You Have Obtained Data on Test Scores and Student-Teacher Ratios $$Y _ { i } = \beta _ { 0 } + \beta _ { 1 } X _ { 1 i } + \beta _ { 2 } X _ { 2 i } + \beta _ { 3 } X _ { 3 i } + u _ { i }$$

Essay

You have obtained data on test scores and student-teacher ratios in region A and region B
of your state.Region B, on average, has lower student-teacher ratios than region A.You
decide to run the following regression $$Y _ { i } = \beta _ { 0 } + \beta _ { 1 } X _ { 1 i } + \beta _ { 2 } X _ { 2 i } + \beta _ { 3 } X _ { 3 i } + u _ { i }$$ where X1 is the class size in region A, X2 is the difference in class size between region A
and B, and X3 is the class size in region B.Your regression package shows a message
indicating that it cannot estimate the above equation.What is the problem here and how
can it be fixed?