老师 为什么proceed from shares不属于NI里的revenue？

老师您好！请问计算器上能对数值（如100）开任意次方吗？如对100开6次方，没找到按键

自由度区间代表的是原假设还是备择假设？

  想问一下为什么LIFO会有higher D/E？ D是不变的，LIFO怎么影响E？

57题中，如果两个是非完全线性是什么样的啊，完全线性不需要增加相同的数量吧，是不是只需要保持一样的斜率？

选项b，只有利息的贷款是什么意思，麻烦老师解释下

什么情况下产生a？

想问一下第三题，还是不太懂

Q. If an investor uses derivatives to make a long investment in commodities, the return earned on margin is best described as: A. convenience yield. B. collateral yield. C. price return. B is correct. Collateral yield is the return on cash used as margin on derivatives used to gain commodity exposure. A is incorrect because the convenience yield (also known as “roll yield”) is the return from rolling forward the maturity of the derivatives position. C is incorrect because price return is the difference between the forward and spot price. 请问老师，这个题目怎么理解？

啥意思？？？！？