老师您好，请问这道题treasury bond future的duration为什么选4.9不是5？

老师您好，请问这道题计算标普500指数期货为什么价格上不乘以250的乘数呢？这里trading at 1025是指数还是价格？谢谢

为什么这里用的都是连续复利，不是bond一般是一般复利吗 后面一道题为什么默认题目给的是一般复利

老师第17题第一，三条怎么翻译理解?最后一条假设里没看到有return distribution has no skewness

老师 我不明白为什么AC不提前行权折现要减去D 不提前行权这个红利不是给short方的嘛 long方拿不到啊

请问老师第13题A，D选项怎么不对，该怎么改

请问老师第11题B选项为什么不对，该怎么理解

请问老师第四题题目和选项是啥意思，没看懂

原版书原文Settlement risk is the risk due to the exchange of cash flows when a transaction is settled. Failure to perform on settlement can be caused by a counterparty default, liquidity constraints, or operational issues. This risk is greatest when payments occur in different time zones.为什么说这种风险不同时区还款时最大呢？两者有什么联系吗？

原版书上这段：Downgrade risk is the risk that the perceived creditwor-thiness of the borrower or counterparty might deteriorate. In general, deteriorated creditworthiness translates into a downgrade action by the rating agencies, such as Standard and Poor's (S&P), Moody's, or Fitch in the United States, and an increase in the risk premium, or credit spread of the borrower. 这里最后一句的意思不就是说credit spread的增加么？那这个是信用风险啊。为什么习题里面有一个credit spread widen following recent bankruptcies要归属为市场风险呢？