Answer: option A
Explanation:
The volume of a cylinder can be calculated with the formula:
![V=\pi r^2h](https://img.qammunity.org/2020/formulas/mathematics/middle-school/2x6jh6ysz6ef85wkmp7armtq6fmfcdu3bh.png)
Where r is the radius and h is the height of the cylinder.
The radius is diameter divided by 2, then:
![r=(18ft)/(2)\\\\r=9ft](https://img.qammunity.org/2020/formulas/mathematics/middle-school/65jpkjvg3hbovwjuawuknefng8dhlwcxx0.png)
Substitute the radius into the formula. Then you get the following equation that can be used to find V, the volume of the cylinder:
![V=\pi (9)^2h](https://img.qammunity.org/2020/formulas/mathematics/middle-school/8pkh2t7t4okmctees6gl5w7hlt1znm9092.png)