Cuboid With Net
This sketch makes a hexahedron with a top and bottom face parallel.
Adjust h to change the height between the top and the bottom faces.
Adjust A, B, C and D to change the bottom face.
Adjust a_1, b_1 and c_1 ((x,y) position of the top face vertices)
to change the top face.
We're going to use this to make some unfair dice! For Chi-Squared testing...