The density of deer in a forest is the radial function (r) = 150(r 2 + 2)

The density of deer in a forest is the radial function ρ(r) = 150(r² + 2)⁻² deer per square kilometer, where r is the distance (in kilometers) to a small meadow. Calculate the number of deer in the region 2 ≤ r ≤ 5 km.