If X̅ is the mean of a distribution of X, then under usual notation \(\displaystyle\sum_{i=1}^n f_i (x_i - \bar{x})\) is?

If X̅ is the mean of a distribution of X, then under usual notation�

1.	If X̅ is the mean of a distribution of X, then under usual notation \(\displaystyle\sum_{i=1}^n f_i (x_i - \bar{x})\) is?
A.	Mean deviation about mean
B.	Standard deviation
C.	1
D.	0
Answer» E.