function toggleLayer(whichLayer)
{var elem,vis;if(document.getElementById)
elem=document.getElementById(whichLayer);else if(document.all)
elem=document.all[whichLayer];else if(document.layers)
elem=document.layers[whichLayer];vis=elem.style;if(vis.display==''&&elem.offsetWidth!=undefined&&elem.offsetHeight!=undefined)
vis.display=(elem.offsetWidth!=0&&elem.offsetHeight!=0)?'block':'none';vis.display=(vis.display==''||vis.display=='block')?'none':'block';}