function show(show_div)
{
     	Layer1.style.visibility='hidden';
   	Layer2.style.visibility='hidden';
   	Layer3.style.visibility='hidden';
   	Layer4.style.visibility='hidden';
   	Layer7.style.visibility='hidden';
	document.all[show_div].style.visibility='visible';
}

function hidediv()
{
     	Layer1.style.visibility='hidden';
   	Layer2.style.visibility='hidden';
	Layer3.style.visibility='hidden';
	Layer4.style.visibility='hidden';
	Layer7.style.visibility='hidden';
}