请问什么是Zero-sum game

选项b收益率和价格的这个关系，老师没太明白。

Wallace, an emerging market bond trader, is holding a 5-year USD Malaysian corporate bond in his book. He is concerned about the risk of his position. Which of the following statements concerning the risk of his position is incorrect? A The corporate bond could be upgraded so that it would have a higher rating than Malaysian sovereign debt, but it is highly unlikely. B Buying protection with a CDS would hedge the corporate bond position against some risks but it would do a poor job of hedging the position if there is a drop in liquidity for emerging market sovereign bonds. C A short position in Ringgits sovereign bond from Malaysia would always help hedge the corporate bond against currency risk if the corporation is an exporter. D A short position in a 5-year US treasury and buying protection on the corporate bond using a CDS would be a better hedge than just buying protection on the corporate bond. 麻烦解释一下c

autocorrelations是自相关的意思 那autocovariancesa是自协方差吗？

贝塔是怎么算的呢？谢谢！

老师好，这题完全没理解，我怎么觉得选a更好

习题解说老师说：价格与市场收益率成反比，这个问题不明白

还是没有太理解本题中的CD选项，overvalue和undervalue，还有就是关于CML，SML公式中的E（R）表示的是预期的收益率还是实际的收益率。

为什么这章的题都没有视频解析了？

为什么不是C不在线上？