Which of the following must be true? I. All the sides of a scalene triangle are of unequal length. II. All the interior angles of a polygon must be acute angles. III. At least one of the interior angles of a concave polygon is a reflex angle.
Which of the following must be true? I. All the sides of a scalene triangle are of unequal length. II. All the interior angles of a polygon must be acute angles. III. At least one of the interior angles of a concave polygon is a reflex angle.