Class Tetrahedron

public class Tetrahedron extends Polyhedron{

// A constructor:

Tetrahedron(double theWidth, double theLength, double theHeight) {

width = theWidth; length = theLength; height = theHeight;

nFaces = 4; nVertices = 4; nEdges = 6;

}

// A different concrete method for the same abstract method:

public double volume() {

return (width * length * height) / 6.0;

}

// This method overrides the parent’s, but calls it, too.

public void describe() {

System.out.print(“(Tetrahedron) “); super.describe();

}