Use the data set GPA1 for this exercise.(i) Use OLS to estimate a model relating colGPA to hsGPA, ACT, skipped, and PC. Obtain the OLS residuals.(ii) Compute the special case of the White test for heteroskedasticity. In the regression of u^2i on colGPAi, colGPA2i, obtain the fitted values, say h^i.(iii) Verify that the fitted values from part (ii) are all strictly positive. Then, obtain the weighted least squares estimates using weights 1/h^i. Compare the weighted least squares estimates for the effect of skipping lectures and the effect of PC ownership with the corresponding OLS esti-mates. What about their statistical significance