function changeBack () {
   document.images.image03.src="../images/sub_nav_arrow_off.gif";
   document.images.image04.src="../images/sub_nav_arrow_off.gif";
   document.images.image05.src="../images/sub_nav_arrow_off.gif";
   document.images.image06.src="../images/sub_nav_arrow_off.gif";
   document.images.image07.src="../images/sub_nav_arrow_off.gif";
   }