Find the Number B Such That the Line $y=b$ Divides the Region Bounded by the Curves

Multiple Choice

Find the number b such that the line $y=b$ divides the region bounded by the curves $y=x^{2}$ and $y=5$ into two regions with equal area.

A) $5^{1 / 2}$
B) $5^{2 / 3}$
C) $\frac{2}{3}$
D) $5^{1 / 3}$
E) $\frac{1}{3}$