老师好，请问R18课后题#21，不是很懂

请问求到了18，19，20，21 时刻的cost，不是应该是18的0时刻就是一开始的价格，不应该等于17end的价值吗。但为什么还需要用18的cost除去1.06. 谢谢

49. Acme Corp. purchased a new stamping machine for $100,000, paid $10,000 for shipping, and paid $5,000 to have it installed in their plant. Based on an estimated salvage value of $25,000 and an economic life of six years, the difference between straight-line depreciation and double-declining balance depreciation in the second year of the asset's life is closest to: A. $7,220. B. $10,556. C. $16,666. 您的答案：C 正确答案：B 得分：0分 解析: Straight line depreciation is (100,000 10,000 5,000 ? 25,000) / 6 = 15,000 each year. Double-declining balance depreciation in the second year is: 115,000 (2/3) (1/3) = 25,556. The difference is $10,556. Remember that salvage value is not part of the declining balance calculation. 这道题计算DDB，我有问题。资产原值（不包含剩余价值）/6年*2=资产原值*1/3（按照1/3来折旧），第二年还剩下5年，资产原值*1/3*2/5哇？

Which of the following statements is most accurate about the responsibilities of an auditor for a publicly traded firm in the United States? The auditor must: A. ensure that the financial statements are free from error, fraud, or illegal acts. B. state that the financial statements are prepared according to generally accepted accounting principles. C. express an opinion about the effectiveness of the company's internal control system 您的答案：C 正确答案：B 得分：0分 解析: For a publicly traded firm in the United States, the auditor must express an opinion as to whether the company's internal control system is in accordance with the Public Accounting Oversight Board, under the Sarbanes–Oxley Act. The opinion is given either in a final paragraph in the auditor's report or as a separate opinion. 这道题是这次的模考题，从答案解释来看，应该选B，所以我有点晕。

老师，这个total debt只含有息负债吗？还有capital是含有有息负债和equity嘛，那为什么A/P不算在里面呢？

反稀释的内涵，作用，怎么执行理解不了，能否通过一点生动的实际故事或者案例讲解

老师您好，德州计算器第三排5个白色按键（TVM五键）中的FV和PV到底代表什么？实例如下： 例如： 有一笔后付年金的r=10%，payment=100，n=3。 那可以算出这笔年金的PV=248.6852，FV=331。 那现在在德州计算器上输入r=10%，FV=331，PV=-248.6852，n=3， 为什么算出来pmt=0？ 在r，n不变的情况下，只有令『PV=-248.6852，FV=0』，或者令『PV=0，FV=-331』,才能算出pmt=100？ TVM那一排五个键里面的FV和PV到底代表年金的现值和终值，还是分别代表T0和Tterminal时刻的除了payment以外的现金流？感觉这里输入的FV，PV的值就是上面年金算出的FV和PV，但他俩其中一个输入了上面算出的值，另一个就要输入0，不然算不出正确的pmt。现在FV和PV两个键输入和输出的数值分别代表什么，完全逻辑混乱了。

老师好，请问R17课后题#17，b选项为什么不对

老师好，请问R16课后题#16，应该怎么理解

老师 请问 为什么折溢平价债券 的CR与r是小于 大于 等于的关系 对着块不太理解其中的原理