From the "Mascot" dataset, define a linear model to predict whether people's attitudes toward the native american mascot (DV = attitudes) are related to their socioeconomic status (IV = SES) - a variable that you will need to create. Create a scale to measure "socioeconomic status" (SES) that is the average of the three variables : MotherEducation, FatherEducation, and Income. No reverse-scoring is needed. Report the alpha reliability of the scale