Answer:
A 162° interior angle at each vertex means that the deflection angle (the amount by which the next side deflects from the course of the current side) is 180°-162°=18°. Since deflecting 360° takes you back to where you started, the number of sides is given by:
n = 360°/DeflectionPerVertex = 360°/18° = 20.
Hence the polygon has 20 sides and 20 vertices.
Explanation: