function live(url, tem_carrinho){
if(tem_carrinho)
    var hgt = 700;
else
    var hgt = 700;

var l = (screen.width-692)/2;
var t = (screen.height-hgt)/2;
var code = 'toolbar=no,location=no,status=no,menubar=no,scrollbars=no,resizable=no,width=742,height=' + hgt + ',left=' + l + ',top=0';
var resizable='no';
window.open(url,'ao_vivo',code);
}