(c) Consider the following model, Y = 8 + 82X2 + 83D + SAD, X+ + ut Suppose that 8, > 0,82 > 0,83 > 0,84 > 0. (1) Find the new equation if D=0. [1.5 Marks (ii) Find the new equation if D= 1. [1.5 Marks) (iii) Draw the regression lines based on questions (i) and (ii). Briefly explain. [6 Marks