if (parseInt(navigator.appVersion)>= 4)
  {
    if (navigator.appName == "Netscape")
    {
        layerStyleRef="layer.";
        layerRef="document.layers";
        styleSwitch="";
    }
    else
    {
    layerStyleRef="layer.style.";
    layerRef="document.all";
    styleSwitch=".style";
    }
  }


function show(a){
 eval(layerRef+'["'+a+'"]'+styleSwitch+'.visibility="visible"');
}

function hide(a){
 eval(layerRef+'["'+a+'"]'+styleSwitch+'.visibility="hidden"');
}



function picv(a){
 document[a].src="../pic/"+a+"_"+a+".gif";
}

function pich(a){
 document[a].src="../pic/"+a+".gif";
}