Today is 1 July, 2019. Carole has a portfolio which consists of two different types of financial instruments (henceforth referred to as instrument A and instrument B). Carole purchased all instruments on 1 July 2011 to create this portfolio, which is composed of 35 units of instrument A and 23 units of instrument B. - Instrument A is a zero-coupon bond with a face value of $100. This bond matures at par. Its maturity date is 1 January 2029. - Instrument B is a Treasury bond with a coupon rate of j2=3.65% p.a. and a face value of $100. This bond matures at par. Its maturity date is 1 January 2022. What is the duration of instrument B? Express your answer in terms of years and round your answer to three decimal places. Assume a yield rate of j2=4.19% p.a. a. 4.823 years b. 5.735 years c. 2.868 years d. 2.411 years