function toggleLayer(whichLayer)
{
  if (document.getElementById)
  {
// this is the way the standards work
    var style2 = document.getElementById(whichLayer).style;
    style2.display = style2.display? "":"block";
  }
  else if (document.all)
  {
// this is the way old msie versions work
  var style2 = document.all[whichLayer].style;
  style2.display = style2.display? "":"block";
  }
  else if (document.layers)
 {
// this is the way nn4 works
  var style2 = document.layers[whichLayer].style;
  style2.display = style2.display? "":"block";
}
}// JavaScript Document