老师，这道题目不太理解，求解释

老师能再解释下Value of putable bond=Value of pure bond + put option和Value of callable bond=Value of pure bond - call option吗？

对于putable bond，yield越大，more convexity，不是应该选C吗？难道more convexity不是high convexity的意思吗？

答案肯定要选一个，所以不算WACC，直接选一个IRR高的不就成了 吗

请问PV、FV、PMT之间的正负符号关系是怎样的？如果PV是0，那么FV和PMT之间的符号一定是相反的吗？

lower bound是什么意思？

A call option with a strike price of 60 will expire in 80 days. No cash payments will be made by the underlying asset over the life of the option. If the underlying asset price is 70 and the risk-free rate of return is 5.0 percent, the lower bound for an American call option and a European call option, respectively, are closest to A the lower bound for an American call option is 10; the lower bound for a European call option is 10.64. B the lower bound for an American call option is 10.64; the lower bound for a European call option is 10. C the lower bound for an American call option is 10.64; the lower bound for a European call option is 10.64. 为什么在题目里美式与欧式的价格会一样？还有一点就是为什么这里美式不提前行权？

01.单选题 Which of the following is least likely an appropriate use of the CFA designation? A. Jeremy Salyers, as a CFA charterholder, expects to outperform the market because CFA charterholders have on average outperformed their peers. B. Jeremy Salyers, CFA. C. Jeremy Salyers has earned the CFA designation by passing three exams, all three on his first attempts. 这个答案选A，但我觉得C也不对啊，通过考试就能获得CFA的designation吗？不是还需要有48个月的相关工作经验，以及两个持证人的推荐才可以使用CFA的title吗？

c答案，有效久期不是用市场上观测到的v-和v+来计算的吗？观测到的不就是past price吗？

视频里好像没有讲Marshall-Lerner condition这一块的东西