// Show and hide the appropriate layers

function show(on,off,divId) {
  if (document.getElementById) {
      document.getElementById(on).style.visibility='visible';
      document.getElementById(off).style.visibility='hidden';
  }
  else if (document.all) {
      document.all[on].style.visibility = "visible";
      document.all[off].style.visibility = "hidden";
  }
  else if (document.layers) {
      document.layers[divId].document.layers[on].visibility = "show";
      document.layers[divId].document.layers[off].visibility = "hide";
   }
   else {
     return false;
   }
}