The triangles are shown to be similar, therefore

The answer is 9 units
Cot(x)sec(x) =
(cos(x)/sin(x))(1/cos(x))=
cos(x)/(sin(x)cos(x)) =
1/sin(x) =
csc(x)
A bell curve describes a random distribution where at either end is a low amount with the middle representing a higher amount of points.
So at either ends are “extremes” were someone scored really low or really high. The middle presents the average where most people will score