function checkWebpoll(formId){
  var checked=false;
  for (var i = 0; i < document.forms[formId].webpollAnswer.length; i++){ 
    if (document.forms[formId].webpollAnswer[i].checked){ 
      var checked=true;
      break;
    }
  }
  if (!checked){
    alert('U dient keuze te maken om te stemmen')
    return false;
  }
}