Question 4 (1 point) Suppose that the duration of ABCs U.S. pension liability is estimated at 8 years. ABC wants its bond investments in the pension fund to hedge all of the PBO's exposure to the discount rate. If the PBO is $2.5 billion, the fair value of pension assets are $2.4 billion, and the fund is 90% in bonds and 10% in stocks, what duration of bonds need to be purchased? 10.27 years 9.26 years O 10.51 years O 9.89 years 9.69 years 10.84 years