Betsy a recent retiree requires $5000 per year in extra income. She has $70,000 to invest and can invest in B rated bonds paying 13% per year or in a CD paying 5% per year. How much money should be invested in each to realize exactly $5000 in interest per year?

The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. according to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?