3. The average monthly return on a long term debt portfolio is 5.08% and is normally distributed. The standard deviation is 2.31%.

a) In any given month, what percentage (to the nearest whole percent) of the returns will be between 0.46% and 9.70% ?

b) With what level of confidence (to the nearest whole percent) would we expect the returns to be between 2.77% and 7.39%?

c) What values would we expect the returns to be between 99.73% of the time?