Tuddenha and Snyder obtained the following results for 66 California boys at ages 6 and 18.

average height at 6 is 3 ft. 10 inches/standard deviation =1.7 inches

average height at 18 is 5 ft. 10 inches/standard deviation=2.5 inches

r=0.80

a.) Find the r.m.s. error for the regression prediction of height at 18 from height at 6.

b.) Find the r.m.s. error for the regression prediction of height at 6 from height at 18.