function changeDIVmerk(selObj) {
  var divObj;
  selValue = selObj.options[selObj.selectedIndex].value;
  if(document.all) {
    if(selValue=="Anders..") {
      window.divAnders.style.visibility = "visible";
    } else {
      window.divAnders.style.visibility = "hidden";
    }
  } else {
    if(selValue=="Anders..") {
      document.layers["divAnders"].style.visibility = "show";
    } else {
      document.layers["divAnders"].style.visibility = "hide";
    }
  }
}
function changeDIVsoort(selObj) {
  var divObj;
  selValue = selObj.options[selObj.selectedIndex].value;
  if(document.all) {
    if(selValue=="Monitor") {
      window.divMonitor.style.visibility = "visible";
    } else {
      window.divMonitor.style.visibility = "hidden";
    }
  } else {
    if(selValue=="Anders..") {
      document.layers["divAnders"].style.visibility = "show";
    } else {
      document.layers["divAnders"].style.visibility = "hide";
    }
  }
}