function change_class(id,newClass){identity=document.getElementById(id);identity.className=newClass}function show(obj_id){obj=document.getElementById(obj_id);obj.style.visibility='visible'}function hide(obj_id){obj=document.getElementById(obj_id);obj.style.visibility='hidden'}function display(obj_id,action){obj=document.getElementById(obj_id);obj.style.display=action}function opacity(obj_id,opacity){obj=document.getElementById(obj_id);obj.style.MozOpacity=0.75;obj.filters.alpha.opacity=75}function img_swap(imgName){if(version=="n3"){imgOn=eval(imgName+"h.src");document[imgName].src=imgOn}}function img_restore(imgName){if(version=="n3"){imgOff=eval(imgName+"n.src");document[imgName].src=imgOff}}