Your eccentric Aunt Claudia has left you $50,000 in BP shares plus $50,000 cash. Unfortunately, her will requires that the BP stock n be sold for one year and the $50,000 cash must be entirely invested in one of the stocks shown below. a. Calculate the portfolio variance for seven different portfolios. (Use decimals, not percents, in your calculations. Do not round intermediate calculations. Enter your answers as a decimal rounded to 5 places.) b. What is the safest attainable portfolio under these restrictions? Complete this question by entering your answers in the tabs below. Calculate the portfolio variance for seven different portfolios. Note: Use decimals, not percents, in your calculations. Do not round intermediate calculations. Enter your answers as a decimal rounded to 5 places