A 30 year 9% coupon bond currently sells for $100. A 30 year 3% coupon bond with exactly the same coupon dates and maturity currently sells for $50. both bonds have $100 as the principal at maturity. coupon is paid once a year and use continuous compounding. what is the 30 year zero rate? calculate the percentage return per year annum, round to two points below decimal in percentage( for example 10.05).