Please read the following table in HTML format from a webpage and then answer the question in detail according to the table. Each table cell is defined by a <td> and a </td> tag. Each table row starts with a <tr> and ends with a </tr> tag. 'rowspan=m' and 'colspan=n' represents a cell spaning over 'm' rows and 'n' columns.

Webpage title:
List of Berlin U-Bahn stations
Table title:
L
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Station </th><th colspan=1 rowspan=1 > Line </th><th colspan=1 rowspan=1 > Opened </th><th colspan=1 rowspan=1 > Situation </th></tr>
<tr> <td colspan=1 rowspan=1 > Leinestraße </td><td colspan=1 rowspan=1 > U8 </td><td colspan=1 rowspan=1 > 4 August 1929 </td><td colspan=1 rowspan=1 > underground </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=2 > Leopoldplatz </td><td class="highlighted"  colspan=1 rowspan=1 > U6 </td><td colspan=1 rowspan=1 > 8 March 1923 </td><td colspan=1 rowspan=2 > underground </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > U9 </td><td colspan=1 rowspan=1 > 28 August 1961 </td></tr>
<tr> <td colspan=1 rowspan=1 > Lichtenberg </td><td colspan=1 rowspan=1 > U5 </td><td colspan=1 rowspan=1 > 21 December 1930 </td><td colspan=1 rowspan=1 > underground </td></tr>
<tr> <td colspan=1 rowspan=1 > Lindauer Allee </td><td colspan=1 rowspan=1 > U8 </td><td colspan=1 rowspan=1 > 24 September 1994 </td><td colspan=1 rowspan=1 > underground </td></tr>
<tr> <td colspan=1 rowspan=1 > Lipschitzallee </td><td colspan=1 rowspan=1 > U7 </td><td colspan=1 rowspan=1 > 2 January 1970 </td><td colspan=1 rowspan=1 > underground </td></tr>
<tr> <td colspan=1 rowspan=1 > Louis-Lewin-Straße </td><td colspan=1 rowspan=1 > U5 </td><td colspan=1 rowspan=1 > 1 July 1989 </td><td colspan=1 rowspan=1 > at grade </td></tr>
</table>
Question:
Which subway lines are interchangeable at Leopoldplatz station?
Answer:
Leopoldplatz is a Berlin U-Bahn station which serves as an interchange between the lines U6 and U9.