Question 19 2.27 Find the standard deviation of returns using the following data: What is the standard deviation of returns (only standard deviation choices are given; so, once you get standard deviation calculated - choose the answer) Recession period Probability is 0.4 Expected return on stock: -15% Expected return: +10% Expected return: +20% Normal economy Boom economy Probability: 0.2 Probability: 0.4 18.7% 12.3% 20.4% 15.9%