the numbers provided by fourth bank of duration are in thousands of dollars. treasury bill $90 time deposits $1,100 treasury notes $55 fed funds sold $230 treasury bonds $176 demand deposits $2,500 loans $4,679 equity $1,170 notes: all treasury bills have six months until maturity. one-year treasury notes are priced at par and have a coupon of 7 percent paid semiannually. treasury bonds have an average duration of 4.5 years and the loan portfolio has a duration of 7 years. time deposits have a 1-year duration and the fed funds duration is 0.003 years. fourth bank of duration assigns a duration of zero (0) to demand deposits. what is the duration of the bank's treasury portfolio?