股票百题进阶题最后一道，的分母无法理解，这个含借来的资金

这道题怎么会有个equity,这部分有借来的资金部分，不应该作分母

老师,请问这道题选项A为什么不正确?

estimate 是估计未来的意思吗？ 不可以说是估计过去发生的吗？感觉怪怪的。

12题表格里的这么多项怎么判断用那项不用哪项啊？

第12题，Px前系数是负的，交叉弹性代入时是正的？

这题答案c里的$500,000是题中的那个$500,000selling cost吗？

Q. An investor writes a put option on FTSE 100 Index futures. Which of the following best describes the investor’s position with respect to the put contract and her exposure to the underlying index future, respectively? A.Long, short B. Short, long C.Short, short B is correct. The investor has written a put contract, which means she is short the option. She, therefore, must satisfy the obligation to purchase the asset if requested to do so by the put owner. The investor has a long exposure to the risk of the underlying index future because she benefits when its quoted price increases—that is, when the put declines in value (or suffers a loss when its quoted price decreases as the put increases in value). 请问这道题write a put option 是什么意思？是 short put 吗？如果是的话，那敞口应该是short吧？

老师，这个是为什么

老师，这个题为什么分子上不减去本金