A cone
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The original answer also had "Cube", which is obviously wrong!
the solid that has two circular bases is a cylinder
Solid figures are normally classed as 3 dimensional objects
Decagon, if a plane figure or decahedron, if a solid.
you can name a vertex with b
It is the vertex. It can also be called the apex but that has a connotation of being the top-most point and so is not appropriate when both nappes are concerned.
cylinder
the solid that has two circular bases is a cylinder
A vertex is the name of a corner on a solid where three or more faces meet (plural = vertices).
Vertex mate :) 3 or more is a vertex
vertex
vertex
vertex
That is a vertex.
a vertex
A vertex.
The vertex or apex
VERTEX