expense的解释没有读懂

Module 3-官网习题-Question 40-为什么在weak-form efficient market情况下，无法通过trading by looking at patterns of prices and volume from the past 来 earn abnormal profits?

Module 3-官网习题-Question 36-1.答案中的这个公式，哪儿得来的？书上第几页有？Gross return = Net return + Fees and expenses？2.为什么systematic risk=15%? 书上第几页有这个知识点？

Module 3-官网习题-Question 35-C选项答案的第3-4行，为什么 The semi-strong-form of market efficiency also encompasses the weak form？这句话怎么理解？

老师好，expected return on plan assets 400 这项为什么算在抵减expense而不算在OCI或者pension assets？

这道题的知识在王者班这一节课有提及吗？好像和课程内容无关联

Module 3-官网习题-Question 33-1.A选项答案这句话，不太能理解？The semi-strong-form efficiency assumes that prices reflect all publicly known and available information, and therefore efforts to analyze publicly available information is futile. w为什么efforts to analyze publicly available information is futile? 2. C选项答案后半句话不能理解，什么意思？什么叫“leave alone semi-strong-form efficiency.”?更不用说半强势有效市场了？

Module 3-官网习题-Question 32-B选项，错在哪儿？书2022-P243不是明确写着Such trading activity contributes to market efficiency? 如截图2所示

Module 3-官网习题-Question 30-C选项答案解释没明白，respond over time不等同于reflect information quickly （书2022-P237-最后一段标黄，如截图2所示）？

可以给出一个现实中使用fair value hedge的案例吗？只听概念还是没有印象