6.25 The following balance sheet information is available (amounts in thousands of dollars and duration in years) for a financial institution: Amount Duration T-bills $90 0.50 T-notes 55 0.90 T-bonds 176 X Loans 2,724 7.00 Deposits 2,092 1.00 Federal funds 238 0.01 Equity 715 Treasury bonds are five-year maturities paying 6 percent semiannually and selling at par. a. What is the duration of the T-bond portfolio