I sent them a picture explaining how to tell if one face was more horizontal in xyz space with +z axis being up.
If they calculate for the 4 faces of the tetrahedron (4 triangles) as shown below and compare, then they could figure out which face was the most horizontal ... I think.
If they calculate for the 4 faces of the tetrahedron (4 triangles) as shown below and compare, then they could figure out which face was the most horizontal ... I think.