1
a cone has 1 curvedsurface.
A cone only has a single curve. It is a single-faced form with a point and no proper edges with a continuous curve.
ONE
A cone has one curved surface.
A cone has either one or two surfaces and either one or no edges.
It has one.
1
one
A cone has two surfaces, one vertex and no edges.
1 edge and 2 surfaces
ther is 20 surfaces on a cone because the is 1 on it sharp part * * * * * In fact, one flat surface (and one curved one).
An empty cone (like an ice-cream cone) doesn't have any flat surfaces. It has two curved surfaces, one outside and one inside. A solid cone has a flat base, and one other curved surface.