Answer:
[tex]972\pi~ \text{in}^3[/tex]
Step-by-step explanation:
[tex]\text{Volume of sphere} = \dfrac 43 \pi r^3 \\\\\\~~~~~~~~~~~~~~~~~~~~~~~~=\dfrac 43 \pi \left( \dfrac d{2} \right)^3\\\\\\~~~~~~~~~~~~~~~~~~~~~~~~=\dfrac 43 \pi \cdot \left(\dfrac{18}{2}\right)^3\\\\\\~~~~~~~~~~~~~~~~~~~~~~~~=\dfrac{4\pi}3 \cdot 9^3 \\\\\\~~~~~~~~~~~~~~~~~~~~~~~~=972\pi~ \text{in}^3[/tex]
