function MM_showHideLayers() {
    var i,p,v,obj,args=MM_showHideLayers.arguments;
    for (i=0; i<(args.length-2); i+=3)
    with (document) if (getElementById && ((obj=getElementById(args[i]))!=null)) { v=args[i+2];
    if (obj.style) { obj=obj.style; v=(v=='show')?'block':(v=='hide')?'none':v; }
    obj.display=v; }
}