An illustration of a young girl sitting on a bench next to a cat and reading a book upside down.

Girl Sitting on Bench Reading Book with Cat

An illustration of a young girl sitting on a bench next to a cat and reading a book upside down.

The blue and yellow macaw is a group of large parrots, here hanging upside down from a tree branch.

Blue and Yellow Macaw

The blue and yellow macaw is a group of large parrots, here hanging upside down from a tree branch.

Illustration of a hollow right decagonal pyramid. The base is a decagon and the faces are isosceles triangles. The pyramid is inverted, meaning that the vertex is at the bottom and the base is on top.

Inverted Decagonal Pyramid

Illustration of a hollow right decagonal pyramid. The base is a decagon and the faces are isosceles…

Illustration of a hollow right hexagonal pyramid. The base is a hexagon and the faces are isosceles triangles. The pyramid is inverted, meaning that the vertex is at the bottom and the base is on top.

Inverted Hexagonal Pyramid

Illustration of a hollow right hexagonal pyramid. The base is a hexagon and the faces are isosceles…

Illustration of a hollow right nonagonal pyramid. The base is a nonagon and the faces are isosceles triangles. The pyramid is inverted, meaning that the vertex is at the bottom and the base is on top.

Inverted Nonagonal Pyramid

Illustration of a hollow right nonagonal pyramid. The base is a nonagon and the faces are isosceles…

Illustration of a hollow right octagonal pyramid. The base is an octagon and the faces are isosceles triangles. The pyramid is inverted, meaning that the vertex is at the bottom and the base is on top.

Inverted Octagonal Pyramid

Illustration of a hollow right octagonal pyramid. The base is an octagon and the faces are isosceles…

Illustration of a hollow right rectangular pyramid. The base is a rectangle and the faces are isosceles triangles. The pyramid is inverted, meaning that the vertex is at the bottom and the base is on top.

Inverted Rectangular Pyramid

Illustration of a hollow right rectangular pyramid. The base is a rectangle and the faces are isosceles…

Illustration of a hollow right heptagonal (septagonal) pyramid. The base is a heptagon and the faces are isosceles triangles. The pyramid is inverted, meaning that the vertex is at the bottom and the base is on top.

Inverted Septagonal/Heptagonal Pyramid

Illustration of a hollow right heptagonal (septagonal) pyramid. The base is a heptagon and the faces…

Illustration of a hollow right heptagonal (septagonal) pyramid. The base is a heptagon and the faces are isosceles triangles. The pyramid is inverted, meaning that the vertex is at the bottom and the base is on top. The hidden edges are shown in this drawing.

Inverted Septagonal/Heptagonal Pyramid

Illustration of a hollow right heptagonal (septagonal) pyramid. The base is a heptagon and the faces…