math
posted by Emi .
A bond has an average return of 6.8 percent and a standard deviation of 4.6 percent. What range of returns would you expect to see 68 percent of the time?
a. 2.2 percent to 11.4 percent
b. 4.6 percent to 11.4 percent
c. 4.6 percent to 22.8 percent
d. 11.4 percent to 22.8 percent
e. 11.4 percent to 16.0 percent

In a normal distribution, 68% of the time scores are within μ±1SD (6.8±4.6). You can do the math.
I hope this helps. Thanks for asking.