function GetLayerStyle(layerID)
{
	var s;
	if( navigator.appVersion.search( "(MS)?IE" ) > -1 )
		s = ( document.all[layerID] )? document.all[layerID].style : null ;
	else
	{
		var d=document.getElementsByTagName("div");
		s = ( d[layerID] )? d[layerID].style : null ;
	}
	return s;
}
function ShowLayer(layerID)
{
	var	s=GetLayerStyle(layerID);
	s.visibility='visible';
}

function HideLayer(layerID)
{
	var	s=GetLayerStyle(layerID);
//	alert(s+layerID);
	s.visibility='hidden';
}