ns = (document.layers)? true:false
ie = (document.all)? true:false

function show(id) {
	if (ns) document.layers[id].visibility = "visible"
	else if (ie) document.all[id].style.visibility = "visible"
}

function hide(id) {
	if (ns) document.layers[id].visibility = "hidden"
	else if (ie) document.all[id].style.visibility = "hidden"
}