How many vertices ar ethere in a tetrahedron?

Answer 1

"Vertices" means corners.

"Tetra" means four and "hedron" means side, so a tetrahedron is a four sided object. A tetrahedron looks like pyramid. Each side is a triangle.

The bottom of a tetrahedron is a triangle, and a tetrahedron goes up to a point at the top. The three corners of the triangle at the bottom plus the point at the top gives you a total of four corners.