Answer
$9.425\text{ m}^2$
Work Step by Step
Here, $r$ denotes the radius of the sector of the circle.
The Area $A$ of sector can be computed using the formula
$A=\frac{\theta}{360}\cdot \pi \cdot r^2$
where $\theta$ is the central angle measure in degrees.
Hence, here we have
$A=\frac{120}{360}\cdot \pi \cdot 3^2=3\pi\approx9.425\text{ m}^2$