Question 3 You are considering investing in DDC stock. Your broker reports to you the following information on retrospective returns Ri, and the stock price Pi. Year i 2017 2018 2019 2020 Ri 0.30 0.20 -0.10 0.15 Pi $2.20 $1.80 $2.08 $2.00 a) Indicate the appropriate formula, with the values included, to compute the standard deviation of these ex-post returns, and then calculate it (NOTE: You do not have to use the table method illustrated in the lectures). (2 marks) b) Using the dividend growth model, find was the dividend received in 2021? (2 marks)