Let the daily returns of a certain stock on 16, 17 and 18 November 2020 be 10.20%, -15.30% and 12.88%. Further let the closing prices of the stock on 18 and 19 November 2020 be $50.2 and $42.7. (a) Estimate 20 November 2020's volatility using the approximate approach. (3.5 marks) (6) What will be 23 November 2020's estimate of the volatility using the EWMA model with the parameter i of 0.15. if 20 November's closing price of the stock is $40.4? (3 marks) (c) Why do we skip to estimate 21, 22 November 2020's volatilities in part (b)? (0.5 mark) Let the daily returns of a certain stock on 16, 17 and 18 November 2020 be 10.20%, -15.30% and 12.88%. Further let the closing prices of the stock on 18 and 19 November 2020 be $50.2 and $42.7. (a) Estimate 20 November 2020's volatility using the approximate approach. (3.5 marks) (6) What will be 23 November 2020's estimate of the volatility using the EWMA model with the parameter i of 0.15. if 20 November's closing price of the stock is $40.4? (3 marks) (c) Why do we skip to estimate 21, 22 November 2020's volatilities in part (b)? (0.5 mark)