The Density of a Rod 9 Meters Long Is $\sqrt { x }$

Multiple Choice

The density of a rod 9 meters long is $\sqrt { x }$ kg/m at a distance of x meters from one end of the rod. Find the average density of the rod.

A) 6
B) $\frac { 4 } { 3 }$
C) 3
D) 1
E) 2
F) $\frac { 16 } { 3 }$
G) 4
H) $\frac { 8 } { 3 }$