public class TestDisk { 
 
  public static void main(String[] args) { 
    Disk saucer = new Disk(10, 0.02); 
 
    System.out.println("Disk radius: " + saucer.getRadius()); 
    System.out.println("Disk surface area: " + saucer.area()); 
    System.out.println("Disk volumn: " + saucer.volumn()); 
 
    Disk plate1 = new Disk(12, 0.05); 
    Disk plate2 = new Disk(12, 0.07); 
    if (plate1.equals(plate2)) {   
      System.out.println("objects are equal "); 
    } else { 
      System.out.println("Objects are not equal "); 
    } 
    System.out.println(plate1); 
    System.out.println(plate2); 
  }
}