The above shape is called a menger sponge.
It's been sliced through the center by a plane perpendicular to the long diagonal.
What type of shape is left on the cross section?
- Since this is a tier two menger sponge \((M_2)\) there will be two different sizes of the same shape.
- Do not consider the big hexagon on the outside, the one you get from slicing a regular cube. Just consider what shape is on the inside of the hexagon.