Help Hofstadter Hard Seltzer has three-year 7.2% coupon bonds outstanding. These bonds have a face value of $1,000, make semiannually coupon payments and have a yield to maturity of 6.0%. Calculate the duration of Hofstadter's bonds. What is the duration of these bonds if the yield to maturity is 10.0%? (Do not round intermediate calculations. Round your answers to 4 decimal places.) Years 6% YTM 10% YTM Years