6. The data sets APPL. csv and JNJ. csv contain the adjusted closing prices of Apple Inc and Johnson & Johnson from Jan. 1, 2000 to September 8, 2016. Use R to answer the following questions. 1 (a) Do the log returns of Apple Inc, and Johnson & Johnson follow a normal distribution? (b) Compare the tails of the log returns of Apple Inc and Johnson & Johnson with a t- distribution with 4 degrees of freedom. (c) Compare the distributions of the log returns of Johnson & Johnson during the 2008 financial crisis (index: 2063:1812, from 7/1/08 -6/30/09) with those two years after the financial crisis (index: 1306:1, from 7/1/11 -9/8/16) via i. side-by-side boxplots, ii. side-by-side histograms, iii. a QQ-plot. (d) What is the appropriate degree of freedom of the t-distribution for modeling the log returns of the Apple Inc stock two years after the financial crisis (index: 1306:1, from 7/1/11 - 9/8/16)? Provide a QQ-plot and a histogram with overlayed density of the best fitting t-distribution