function Get_Obj(id) {
var o = new Object();
o.o = (document.getElementById) ? document.getElementById(id) :
document.layers ? document.layers[id] :
document.all ? document.all[id] : null;
o.s = document.layers ? o.o : o.o.style;
return o;
}

function showLayer(id) {Get_Obj(id).s.visibility = 'visible';}
function showLayers() {for (var i=0; i<arguments.length; i++) showLayer(arguments[i]);}
function hideLayer(id) {	Get_Obj(id).s.visibility = 'hidden';}
function hideLayers() {	for (var i=0; i<arguments.length; i++) hideLayer(arguments[i]);}