Summer Storme is analyzing an investment. The expected one-year return on the invest-

ment is 20 percent. The probability distribution of possible returns is approximately normal with a standard deviation of 15 percent.

a. What are the chances that the investment will result in a negative return?

b. What is the probability that the return will be greater than 10 percent? 20 percent?

30 percent? 40 percent? 50 percent?