3. (Descriptive statistics) Here is the monthly stock price data for Ford and GM: A B C 1 PRICES FOR FORD AND GM STOCK Date 2 Ford GM 3 2013-11-01 1.77 35.82 4 2013-12-02 1.67 37.47 5 2014-01-02 1.65 39.23 6 2014-02-03 1.65 33.77 7 2014-03-03 1.71 34.69 8 2014-04-01 1.81 33.19 9 2014-05-01 1.65 33.73 10 2014-06-02 1.34 33.69 11 2014-07-01 1.19 36.63 12 2014-08-01 1.27 32.59 13 2014-09-02 1.28 33.91 14 2014-10-01 1.32 31.94 15 2014-11-03 1.24 30.65 16 2014-12-01 1.15 32.38 17 2015-01-02 1.03 34.56 2015-02-02 0.95 32.84 18 19 2015-03-02 0.94 37.3 20 2015-04-01 0.81 36.74 lio Analysis and the Capital Asset Pricing Model a. Calculate the monthly returns for each firm. b. Calculate the covariance between returns of Ford and GM