Can someone show me how to solve this?

astern Electric currently pays a dividend of $1.70 per share and sells for $27 a share. a. If investors believe the growth rate of dividends is 5% per year, what rate of return do they expect to earn on the stock? Note: Do not round intermediate calculations. Enter your answer as a percent rounded to 2 decimal places. b. If investors' required rate of return is 15%, what must be the growth rate they expect of the firm? Note: Do not round intermediate calculations. Enter your answer as a percent rounded to 2 decimal places. c. If the sustainable growth rate is 3% and the plowback ratio is 0.3 , what must be the rate of return earned by the firm on its new investments? Note: Enter your answer as a percent rounded to 2 decimal places