Volume of a cylinder is πr²h. That is the area of the circular base times the height. Radius 3 and height 10: 90π. Solids as a set are in solid geometry.
Base, then height
Find the radius of the circle, square it, multiply by π, then multiply by how tall the cylinder is. If you are given the diameter, halve it first. If you are given circumference, get r from C = 2πr, then plug in. Do not use 2πr as if it were the base area.
The circular base itself is in circumference and area. Surface area is a different count of faces, in surface area. Formulas as a set are in ACT Math formulas.
The bottom line
πr² for the base, then times h. Diameter is not the radius.
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