为什么AD-AS曲线横坐标是real GDP？老师上课时讲了结论没讲原因

22 Increased household wealth will most likely cause an increase in: A household saving. B investment expenditures. C consumption expenditures. 这一题为什么不选B？如果按照解释总需求曲线为什么往下的wealth effect会导致投资增加，那应该选B啊，这个题目中的wealth effect和总需求影响因素的wealth effect不是同一个吗？

为什么影响AS曲线的因素中，公司税收只是影响短期AS曲线？

18 In an industry comprised of three companies, which are small-scale manufacturers of an easily replicable product unprotected by brand recognition or patents, the most representative model of company behavior is: A oligopoly. B perfect competition. C monopolistic competition. 为什么不选C？

6 Companies most likely have a well-defined supply function when the market structure is: A oligopoly. B perfect competition. C monopolistic competition. 什么叫well-defined supply function?为什么只有完全竞争市场是well-defined supply function?其中3种为什么不是？

25 The short-term shutdown point of production for a firm operating under perfect competition will most likely occur when: A price is equal to average total cost. B marginal revenue is equal to marginal cost. C marginal revenue is equal to average variable costs. 这一题C选项MR=AVC是短期关停点，基础课讲的是AR=AVC，是因为在完全竞争市场下MR=AR所以MR=AVC是短期关停点吗？那对于非完全竞争下是MR=AVC呢还是TR=TVC是短期关停点？

24 The short-term breakeven point of production for a firm operating under perfect competition will most likely occur when:A price is equal to average total cost.B marginal revenue is equal to marginal cost.C marginal revenue is equal to average variable costs.1）这一题是怎么的出来的？已知短期盈亏平衡点是AR=ATC，因为任何市场下P=AR，所以P=ATC吗？2）另外我看到原版书上写在完全竞争和非完全竞争下的盈亏平衡点都是AR=ATC，这个对吗？原版书：A firm is said to break even if its TR is equal to its TC. It can also be said that a firmbreaks even if its price (AR) is exactly equal to its ATC, which is true under conditionsof perfect and imperfect competition.3）题目中如果说的average cost是默认为average total cost吗？

老师您好，第13题中，请问为什么I/Y是算EAR而不是直接用题目中给的4%呢？为什么“每一个小区间上的利率是每一年的收益率”？谢谢老师

这个不用考虑key rate duration 哇？

老师，B选项中的成比例变动是什么意思？是指标的资产价格每变动一单位，收益都变动相同单位？