A tetrahedron is a polyhedron consisting of four equilateral triangles.
![A tetrahedron is a polyhedron consisting of four equilateral triangles class=](https://us-static.z-dn.net/files/d83/27c8e6020eb0031bdac7d66db3de5de2.jpg)
Answer:
the second one
Step-by-step explanation:
because if you think it how it folds the second one doesnt form a tetrahedron.You can try it by drawing it in a letter then cutting it to see which forms a shape and which doesnt.