Tryit Editor v2.9

Edit This Code:
<!DOCTYPE html>
<html>
<head>
<style>
td, th {
    border: 1px solid black;
}
</style>
</head>
<body>

<table id="myTable" style="border-collapse:collapse;">
  <tr>
    <th>Month</th>
    <th>Savings</th>
  </tr>
  <tr>
    <td>January</td>
    <td>$100</td>
  </tr>
  <tr>
    <td>February</td>
    <td>$150</td>
  </tr>
</table>
<br>

<button type="button" onclick="myFunction()">Return border collapse</button>

<script>
function myFunction() {
    alert(document.getElementById("myTable").style.borderCollapse);
}
</script>

</body>
</html>