Answer
$I=0.032W/m^2$
Work Step by Step
To find intensity, the formula relating power, intensity, and distance from a source must be used. This formula is $$I=\frac{P}{A}=\frac{P}{4\pi R^2}$$ Substituting in known values of $P=10.W$ and $R=5.0m$ yields $$I=\frac{10.W}{4\pi (5.0m)^2}=.032W/m^2$$
