None.
A polygon is made up of straight line edges between its vertices. There are the same number of edges as vertices in a polygon.
In the case of a polygon, it is convex if all interior angles are less than 180o.
There are no curved edges in a pentagon. Part of the definition of any polygon is that they have straight edges.
it has 0 curved edges
it has 0 curved edges
There are no curved edges, but it does stack.
there are no curved edges on any triangle.
There are no curved edges on a triangular pyramid.
The answer depends on the number of sides in the polygon.
1
In 3 dimensions, at least, a cube has no curved edges.
there are 4 edges
It depends on the polygon
it has four sides