Standard deviation is the square root of the squared difference between the actual return and the average return. It is a measure of a security's volatility over time. Calculate the risk (standard deviation) for Investment B based on the following information: Investment B has a 30% probability of yielding a 9% return and a 70% chance of having a 3% return. Hint: First, calculate the expected return 2.75% 1.56% 3.14% 4.95%