问题如下：
A zero-coupon bond matures in 15 years. At a market discount rate of 4.5% per year and assuming annual compounding, the price of the bond per 100 of par value is closest to:
选项：
A. 51.30.
B. 51.67.
C. 71.62.
解释：
B is correct.
The price of the zero-coupon bond is closest to 51.67. The price is determined in the following manner:
where:
PV = present value, or the price of the bond
r = market discount rate, or required rate of return per period
N = number of evenly spaced periods to maturity
PV = 51.67
虽然答案做对了，但是美国市场上的零息债券不是都半年计息么？那其实应该N=15*2=30而不是15