The book was likely finished sometime in late 1987 or early 1988]. II.The collapse of Communism in the Balkans. It is likely that Gorbachevâs ideas for liberalizing East European communist states worked out best in the Balkan states of Bulgaria and Romania.
A polygon is a  closed plane figure made of three or more straight line segments. The term originated from ancient Greek polygonon, which breaks down to polus (many) and gonia (angle). A polygon is a closed plane figure made of three or more straight line segments.
A polygon is any closed figure with sides made from straight lines. At each vertex of a polygon, there is both an interior and exterior angle, corresponding to the angles on the inside and outside of the closed figure. Understanding the relationships that govern these angles is useful in various geometrical problems.