Use the following info to answer 4-a and b. Suppose the next month rate of return on a portfolio (worth $1M) is distributed as follows. Return Rate Probability -0.05 -0.03 1% 1.5% -0.01 0.00 0.01 0.03 0.04 0.07 0.10 0.12 2.5 % 5% 10% 20% 25% 20% 10% 5% 4. (5pts) 4.a) What is the probability that the rate of return is less than or equal to 0%? (5pts) 4.b) What is the expected rate of return given that the return is known to be less than or equal to zero