function DisplayForm(ctl, frm){
    document.getElementById("tab_air").className = "";
    document.getElementById("tab_hotel").className = "";
    document.getElementById("tab_car").className = "";
    document.getElementById("tab_vpkg").className = "";
    document.getElementById(ctl).className = "current";
    
    document.getElementById("qs_air").style.display = "none";
    document.getElementById("qs_hotel").style.display = "none";
    document.getElementById("qs_car").style.display = "none";
    document.getElementById("qs_vpkg").style.display = "none";
    document.getElementById(frm).style.display = "";
}