Problem 4 In this problem, you will fit a t-distribution to daily log returns of Siemens, and you will estimate the degrees-of-freedom parameter graphically. The data is contained in the evir package. You can run the following codes to load the data: library (evir) data (siemens) Using theoretical quantiles from t-distributions with degrees of freedom, v = 2, 3, 4, 5, 8, 12, draw QQ-plots for the data siemens respectively. This will give you 6 QQ-plots. Answer the following questions. (a) Do the returns have lighter or heavier tails than a t-distribution with 2 degrees of freedom? (b) Based on the QQ plots, what seems like a reasonable estimate of the degrees-of-freedom parameter