Which shape is described as having a flat base and top with one curved side, but is not a polyhedron?

Which shape is described as having a flat base and top with one curved side, but is not a polyhedron?

• A. Cylinder
• B. Sphere
• C. Pyramid
• D. Torus

Answer: (A)

The shape being described with a flat base and top, one curved side, and not classified as a polyhedron is a cylinder. A cylinder has two parallel flat surfaces (the top and bottom) and a curved surface connecting them. This curved surface does not create vertices or edges that are characteristic of polyhedra, which are three-dimensional shapes with flat polygonal faces. In contrast, a sphere is completely round, lacking flat surfaces entirely, while a pyramid has multiple triangular faces that converge to a point, making it a polyhedron. A torus, which resembles a donut shape, does not have flat bases or tops, but rather a continuous curved surface. Therefore, the characteristics of a cylinder match the provided description perfectly.

The shape being described with a flat base and top, one curved side, and not classified as a polyhedron is a cylinder. A cylinder has two parallel flat surfaces (the top and bottom) and a curved surface connecting them. This curved surface does not create vertices or edges that are characteristic of polyhedra, which are three-dimensional shapes with flat polygonal faces.

In contrast, a sphere is completely round, lacking flat surfaces entirely, while a pyramid has multiple triangular faces that converge to a point, making it a polyhedron. A torus, which resembles a donut shape, does not have flat bases or tops, but rather a continuous curved surface. Therefore, the characteristics of a cylinder match the provided description perfectly.