social media，老师说按照传统媒体来办。请问传统媒体怎么办？

The total number of parameters that fully characterizes a multivariate normal distribution for the returns on two stocks is: A 3. B 4. C 5.

ROE=ROA*FinancialLeverage这公式有问题吧？ ROA = [NetIncome interest（1-TaxRate）] / average total assets 这怎么直接把NetIncome和息前税后利润等价起来？

本视频之后的自我测评无法选择已学会然后提交怎么办？

老师，麻烦解释一下AD曲线的含义和影响因素

10 State the approximate probability that a normal random variable will fall within the following intervals: A Mean plus or minus one standard deviation. B Mean plus or minus two standard deviations. C Mean plus or minus three standard deviations. 老师，没搞明白是啥意思

想问下老师，上课时老师讲到周期性企业在经济好的时候，P/E下降，这是不是因为EPS上升，并且默认每股价格不变得出的结论？同时老师说P/E降低，股票被低估，这个结论怎么推出呀？

You are forecasting sales for a company in the fourth quarter of its fiscal year. Your low- end estimate of sales is €14 million, and your high- end estimate is €15 million. You decide to treat all outcomes for sales between these two values as equally likely, using a continuous uniform distribution. A What is the expected value of sales for the fourth quarter? B What is the probability that fourth- quarter sales will be less than or equal to €14,125,000?

为什么不是用BASE法则算出Ending数：43121 3449.7-10000=36570.7 然后再36570.7*8%=2925.7 ？ 为什么这样不对呢

最后一道例题，求方差时是样本方差还是总体方差，题目中也没说清楚，怎么判断