To find the volume of a spherical fish tank, you can use the formula for the volume of a sphere:
\[ V = \frac{4}{3} \pi r^3 \]
where \( V \) is the volume and \( r \) is the radius of the sphere.
Given the radius \( r = 3 \) inches:
\[ V = \frac{4}{3} \pi (3)^3 \] \[ = \frac{4}{3} \pi (27) \] \[ = \frac{108}{3} \pi \] \[ = 36 \pi \]
Now, using the approximate value of \( \pi \approx 3.14 \):
\[ V \approx 36 \times 3.14 = 113.04 , \text{in}^3 \]
The closest answer to this calculation is:
113.10 in³.