cannonball1.buttonMode = true; // sets mouse pointer to hand
cannonball2.buttonMode = true;
cannonball3.buttonMode = true;

cannonball1.addEventListener(MouseEvent.MOUSE_DOWN, clickToDrag);
cannonball1.addEventListener(MouseEvent.MOUSE_UP, releaseToDrop);
cannonball2.addEventListener(MouseEvent.MOUSE_DOWN, clickToDrag);
cannonball2.addEventListener(MouseEvent.MOUSE_UP, releaseToDrop);
cannonball3.addEventListener(MouseEvent.MOUSE_DOWN, clickToDrag);
cannonball3.addEventListener(MouseEvent.MOUSE_UP, releaseToDrop);

function clickToDrag(event:MouseEvent):void {
event.target.StartDrag();
}

function releaseToDrop(event:MouseEvent):void {
var thisItem:Object = event.target;
   if(thisItem.hitTestObject(targetShip) {
     gotoAndStop(FRAME_NUM)

    } else {
      thisItem.visible = false;
     }
  }
}