posted by Anonymous .
An investment broker reports that the yearly returns on common stocks are approximately normally distributed with a mean return of 12.4 percent and a standard deviation of 20.6 percent. On the other hand, the firm reports that the yearly returns on tax-free municipal bonds are approximately distributed with a mean 5.2 percent and a standard deviation of 8.6 percent. Find the probability that a randomly selected
a. Common stock will give a positive yearly return.