In this problem we will perform simple regression according to the CAPM model. An incomplete code is provided in hw2.r . First, read hw2.r to nd out how to use package "quantmod" to get historical data for stock and treasury bill rate. Pick a stock whose FIRST letter is the same as the FIRST letter of your FIRST name. Use the monthly data from January 2012 to Aug. 2020. Then run a simple linear regression between the excess return of your stock (adjusted log return of your stock - risk free return measured by 3-month t-bill rate) v.s. excess return of the SP500 index ( you can use adjusted log return of the sp500 index - risk free return measured by 3-month t-bill rate).