function show( obj_id, nav_id )
 {
 if ( !document.getElementById){return; }
 var i, obj, parent_node ;
 if ( document.getElementById( obj_id ) )
    {
    obj = document.getElementById( obj_id );
	obj_list = obj.parentNode.getElementsByTagName( obj.tagName );
	for ( i = 0 ; i < obj_list.length ; i++ ){ obj_list.item(i).style.display = "none"; }
	obj.style.display = "block";
	for ( i = 1; i < 6; i++ ) {
		document.getElementById('area_sup');
		}
		document.getElementById(nav_id);
	}
}