a cone
The solid shape you are describing is called a cone. A cone has a circular base and narrows to a single vertex, or apex, at the top. Its curved surface connects the base to the vertex, distinguishing it from other solid shapes.
L shape
The corner of a solid where two faces meet is called a "vertex." In three-dimensional geometry, a vertex is a point where edges converge, and it is one of the key elements in defining the shape of a solid. For example, a cube has eight vertices.
An incomplete shape.
cone
The solid shape you are describing is called a cone. A cone has a circular base and narrows to a single vertex, or apex, at the top. Its curved surface connects the base to the vertex, distinguishing it from other solid shapes.
A cone would fit the given description.
L shape
It could be a pyramid shape
A diagonal in a shape is a straight line from one vertex to another vertex (corner).
A cone has one vertex and one edge.
A pyramid with an irregular pentagon base.
An incomplete shape.
triangle
cone
A cone has one vertex, one edge, and one base.
A cone