The average return for Portfolio A over the past twelve months is 3%, with a standard deviation of 4%. The average return for Portfolio B over this same period is also 3%, but with a standard deviation of 6%. The geometric mean return of Portfolio A is 2.85%. The geometric mean return of Portfolio B is:
A
less than 2.85%.
B
equal to 2.85%
C
不正确greater than 2.85%.
这道题被绕晕了：
问题1 ：离散程度（disperse）和标准差（standard deviation)是否为同一个概念，意思是离散程度越大，那么标准差就越大嘛，这个我在将以里面没有看到相关知识点
问题2：既然2的standard devision更大，那么它的几何平均不是应该更大吗？为什么选A
