If I have stata and an excel file, how would I calculate these problems with a porfolio of stocks where one stock is 50% and the other two are 25%. Could you give me step by step how to go about solving that. I have the stocks on a spreadsheet but I can't post it on here unless you give me a way to do that.

(a) Create a histogram using daily returns for the past 10 years for each of your stocks AND for your portfolio. Do they look like a normal distributions? (Hint: Try small binslength 0.1 percentage points.)

(b) Create a histogram using daily returns for the past 10 years for the S&P 500. Does it look like a normal distribution?