How tall should be the yellow rectangle? 80px or 160px?

Relevant code:

  table
  {
  border-collapse: separate;
  border-spacing: 0px;
  height: auto;
  }

  tr {height: auto;}

  td
  {
  background-color: yellow;
  border: orange solid 20px;
  color: lime;
  height: 100px;
  padding: 30px;
  }

  (...)

  <table>
   <tr><td>X</td></tr>
  </table>