Three friends each own portfolios consisting of a diversified stock index fund and short term risk-free Treasury bills.

4.  Three friends each own portfolios consisting of a diversified stock index fund and short term risk-free Treasury bills.  The risk-free rate of return is Rf = 4% and the stock market index fund has an expected return of Rmbar = 10% with a standard deviation of σm = 6%.

For each friend, find the portfolio weights for each investment (wm and wrf ), the expected portfolio rate of return, and the portfolio standard deviation of return.  

a (12).  Tanya has $50,000 to invest.  She purchases $30,000 in stocks, and puts the rest into T-bills.

b. (12) Bruce has $25,000 to invest.  He borrows an extra $20,000 from his broker at the risk-free rate, and puts all the funds into stocks. 

c. (12) Camille has $9000 to invest.  She puts all her funds in risk-free T-bills.

d. (14) Suppose after the friends invest, a recession occurs and the actual stock market return is  -20%.  What rate of return will each friend actually earn in this circumstance?  Whose portfolio performed best?