Answer:
D. The distance from the mean to an inflection point
Step-by-step explanation:
We rarely encounter the actual formula for the normal PDF. It is ...
In fact, the inflection points are at x = ±1, where the curve changes from being concave downward to concave upward.
So, one standard deviation is the distance from the mean to an inflection point.
Answer: 6
3/4 x 12 =36/4
12 x 1/2=6