function getObject( obj ) {

  // step 1
  if ( document.getElementById ) {
    obj = document.getElementById( obj );

  // step 2
  } else if ( document.all ) {
    obj = document.all.item( obj );

  //step 3
  } else {
    obj = null;
  }

  //step 4
  return obj;
  }


function displayObject(obj, show ) {

  document.getElementById('WSx').style.display = 'none';
  document.getElementById('WSx').style.visibilty = 'hidden';
  document.getElementById('200').style.display = 'none';
  document.getElementById('200').style.visibilty = 'hidden';
  document.getElementById('300').style.display = 'none';
  document.getElementById('300').style.visibilty = 'hidden';
  document.getElementById('400').style.display = 'none';
  document.getElementById('400').style.visibilty = 'hidden';
  document.getElementById('500').style.display = 'none';
  document.getElementById('500').style.visibilty = 'hidden';
  document.getElementById('600').style.display = 'none';
  document.getElementById('600').style.visibilty = 'hidden';


  // step 1
  obj = getObject( obj );
  if (obj==null) return;

  // step 2
  obj.style.display = show ? 'block' : 'none';
  obj.style.visibility = show ? 'visible' : 'hidden';
  }