As a passive manager, you are managing a pension fund which has an obligation to pay a retiring employee $50,000 in year 3 and $40,000 in year 5 . The yield curve is flat at 8%. a) What is the present value of this pension fund? b) What is the duration of this pension fund? c) To immunize the interest rate risk, you plan to construct a bond portfolio so that the duration of your assets is equal to the duration of the pension fund. Suppose only the following zero-coupon bonds are available to invest, what are the right weights of each bond to be invested in this portfolio? d) What is the dollar amount to be invested in bond C and bond D, respectively