Suppose a stock has a 30 percent probability of a 10 percent return, a 50 percent probability of an 8 percent return, and a 20 percent probability of a 15 percent return. What is the standard deviation of returns 9 95 40 Consider the average rates of return for common stocks, government bonds and T-bills for the period 1976-2007 Stocks 13.1% Government Bonds 10.8% Treasury Bills 79% What is the difference between the risk premium on stocks and the maturity premium on government bonds? 3.5 percent 2.3 percent 2.9 percent 5.2 percent Undetermined