It depends on the polygon. A triangle has 3, a square has 4, etc.
18 triangles
Infinitely many. For each integer n (greater than 2), there is a polygon with n sides or n vertices.
All vertex angles (also called "interior angles") of a regular polygon have equal measures. If this regular polygon has n sides, then the sum of all the interior angles is 162° times n. The sum of...
i dont know find out your self
It all depends on what kind of polygon it is. It may have no congruent sides or all congruent sides.