Today is 1 July 2020. Joan has a portfolio which consists of two different types of financial instruments (henceforth referred to as instrument A and instrument B). Joan purchased all instruments on 1 July 2011 to create this portfolio and this portfolio is composed of 28 units of instrument A and 44 units of instrument B. Instrument A is a zero-coupon bond with a face value of 100. This bond matures at par. The maturity date is 1 January 2030. Instrument B is a Treasury bond with a coupon rate of j2 = 2.16% p.a. and face value of 100. This bond matures at par. The maturity date is 1 January 2023. (a) Calculate the current price of instrument A per $100 face value. Round your answer to four decimal places. Assume the yield rate is j2 =4.03% p.a. Select one: a. 46.8562 O b. 47.2049 O c. 47.8003 O d. 68.4516