4. As a statistical consultant, you have been asked to develop a linear

model which shall be given to first year executive MBA students. 
Variable            Name                                                        Description
X1                     Gender                                                      Male or Female
X2                     GMAT Score                                            Score on GMAT Test
X3                     College Degree Previously Earned         Bachelors, Masters, or PhD
Y                       Income                                                      Annual Income in Thousand Dollars
Where 1=Male and 2= Female for X1 and B = Bachelors Degree, M=Master's Degree, and P= PhD for  X3.
 
a.    Given this data, recode the variables so that they may be used as potential predictors for Y in a linear regression model.  Redefine your categorical variables and write them out here. 
 
 
 
b.     Now assume that the influence of a Bachelors Degree on Income may depend on Gender and vice versa. In order to answer this question (does the influence of Bachelor's Degree depend on Gender and vice versa?), write a regression model (using the model from part a ) and describe how you would answer this question with your model.