The volume of the cylinder is ______ cubic feet.

• A. 7.25
• B. 9.42
• C. 11.89
• D. 13.0

Answer: (B)

The volume of a cylinder is found by multiplying the area of its circular base by its height. Since the base is a circle, its area is πr^2, so the volume is V = πr^2h. To compute, you need the radius (or diameter) of the base and the height.

If you’re given a diameter, halve it to get the radius, then plug into V = πr^2h and perform the multiplication. Round the final result to the requested precision.

For a concrete example, take a radius of 1 ft and a height of 3 ft: V = π × (1 ft)^2 × 3 ft = 3π ft^3 ≈ 9.42 ft^3. This shows how the radius (squared) and height determine the final volume. If either dimension changes, the volume changes accordingly, since the base area scales with r^2 and the height scales linearly.