/** Sphere.java -- an example of a class implementing ThreeD.  This means
 *  we must specify both area and volume.
 */
public class Sphere extends Shape implements ThreeD
{
  private double radius;

  public Sphere(String n, double r)
  {
    super(n);
    radius = r;
  }

  // It might be faster to just use radius*radius, rather than
  // calling the pow() function.
  public double findArea()
  {
    return 4.0 * Math.PI * Math.pow(radius, 2.0);
  }

  public double findVolume()
  {
    return 4.0/3.0 * Math.PI * Math.pow(radius, 3.0);
  }
}