xpathを使用して、以下のhtmlからのみ「NationalAeronauticsandSpaceAdministration」の値を取得したい
<table style="margin: 0 5px 0 2px; font-size: 8pt;" class="joaResultsDetailsTable">
<tr>
<td><strong>Department:</strong></td>
<td>National Aeronautics and Space Administration</td>
</tr>
<tr>
<td style="width: 112px;"><strong>Agency:</strong></td>
<td>George C. Marshall Space Flight Center</td>
</tr>
<tr>
<td><strong>Open Period:</strong></td>
<td>9/10/2012 to 9/14/2012</td>
</tr>
<tr>
<td><strong>Who May Apply:</strong></td>
<td>
Current students from education institutions interested in paid opportunities wi...
</td>
</tr>
<tr>
<td style="vertical-align:top;"><strong>Location(s):</strong></td>
<td>Huntsville, Alabama</td>
</tr>
</table>
お手伝いいただければ幸いです