function printPreview(id, cat) {
  var id, cat
  var url="printpreview.php?cat="+cat+"&id="+id
  var title="PrintPreview"
  var option="scrollbars=yes, location=no, status=no, menubar=no, resizable=no, width=700px, height=700px"
  window.open(url, title, option); 
}