Untitled

<!DOCTYPE html>
<html>
 <head>
    <title>Calculator</title>
 </head>
 <body>
    <table border="1" width="40%" height="60%">
      <tr>
        <td colspan="4"  height="100"></td>
      </tr>
      <tr>
        <td height="100"><button type="button">1</button></td>
        <td  height="100"><button type="button">2</button></td>
        <td  height="100"><button type="button">3</button></td>
        <td  height="100"><button type="button">+</button></td>
      </tr>
      <tr>
        <td  height="100"><button type="button">4</button></td>
        <td  height="100"><button type="button">5</button></td>
        <td  height="100"><button type="button">6</button></td>
        <td height="100" ><button type="button">-</button></td>
      </tr>
      <tr>
        <td height="100" ><button type="button">7</button></td>
        <td  height="100"><button type="button">8</button></td>
        <td  height="100"><button type="button">9</button></td>
        <td height="100" ><button type="button">*</button></td>
      </tr>
      <tr>
        <td  height="100"><button type="button">C</button></td>
        <td  height="100"><button type="button">0</button></td>
        <td  height="100"><button type="button">/</button></td>
        <td  height="100"><button type="button">=</button></td>
      </tr>
    </table>
 </body>
</html>