问题如下图：
选项：
A. 
B. 
C. 
解释：
请教，上面的计算式子用计算器怎么按呢？按了几次算出来都不是0.0209啊。
4.18%. 4.50%. B is correct. The formula for calculating this bons yielto-maturity is: PV=PMT(1+r)1+PMT(1+r)2+PMT(1+r)3+⋯+PMT(1+r)39+PMT+FV(1+r)40PV=\frac{PMT}{{(1+r)}^1}+\frac{PMT}{{(1+r)}^2}+\frac{PMT}{{(1+r)}^3}+\cts+\frac{PMT}{{(1+r)}^{39}}+\frac{PMT+FV}{{(1+r)}^{40}}PV=(1+r)1PMT+(1+r)2PMT+(1+r)3PMT+⋯+(1+r)39PMT+(1+r)40PMT+FV where: PV = present value, or the priof the bonPMT = coupon payment per perioFV = future value paimaturity, or the pvalue of the bonr = market scount rate, or requirerate of return per perio111=2.5(1+r)1+2.5(1+r)2+2.5(1+r)3+⋯+2.5(1+r)39+2.5+100(1+r)40111=\frac{2.5}{{(1+r)}^1}+\frac{2.5}{{(1+r)}^2}+\frac{2.5}{{(1+r)}^3}+\cts+\frac{2.5}{{(1+r)}^{39}}+\frac{2.5+100}{{(1+r)}^{40}}111=(1+r)12.5+(1+r)22.5+(1+r)32.5+⋯+(1+r)392.5+(1+r)402.5+100 r = 0.0209 To arrive the annualizeyielto-maturity, the semiannurate of 2.09% must multiplietwo. Therefore, the yielto-maturity is equto 2.09% × 2 = 4.18%. 算出来的就是2.09，为什么答案是b？
算出来的2.09%为何是the semiannurate 而不是annurate?
