Using the data in gpa2.csv, we obtain the following equation for predicting college gpa: colgpa \ =1.493 (.075) + .00149 (.7) sat − .01386 (.00056) hsperc − .06088 (.01650) hsize + .00546 (.00227) hsize2 n = 4, 137, r2 = .278, r¯2 = .277, σˆ = .560. (a) what is the predicted college gpa when sat = 1, 200, hsperc = 30 and hsize = 5 (which means 500)? (b) obtain a 95% confidence interval for the prediction above. (you may need to change the original model to run a new regression.)