The following three defense stocks are to be combined into a stock index in January 2019 (perhaps a portfolio manager believes these stocks are an appropriate benchmark for his or her performance): Price Shares (millions) 1/1/19 1/1/20 1/1/21 Douglas McDonnell 200 $ 70 $ 73 $ 87 Dynamics General 300 51 46 60 International Rockwell 390 80 69 86 a. Calculate the initial value of the index if a price-weighting scheme is used. b. What is the rate of return on this index for the year ending December 31, 2019? For the year ending December 31, 2020?