A company has a dividend record of 1.02 (D-5), 1.08 (D-4), 1.15 (D-3), 1.25 (D-2), 1. 35 (D-1), and 1.5 (D0) for the last six years. Calculate the average dividend growth rate based on the dividend records. (you dont need to calculate the geometric growth rate) If the current stock price P0 is $12, estimated the required rate of returns using dividend growth approach. (hint: use the estimated dividend growth rate to calculate D1)