Parallel lines with a non-perpendicular transversal

Complementary adjacent angles formed by 3 intersecting lines

Concentric triangles with parallel edges

Internally tangent circles

A major arc which is NOT part of a full circle

A license plate with all the digits the same

Circle with 7 or more diameters

Cone or pyramid

Pentagon

Isosceles trapezoid

Quadrilateral that is equilateral but not equiangular

A 3-4-5 triangle

Concave (non-convex) polygon

Equilateral triangle

2 non-perpendicular, bisecting line segments

Octahedron

4-6 rays with a common vertex