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:
100th United States Congress
Table title:
Senate
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > State (class) </th><th colspan=1 rowspan=1 > Vacator </th><th colspan=1 rowspan=1 > Reason for change </th><th colspan=1 rowspan=1 > Successor </th><th colspan=1 rowspan=1 > Date of successor's formal installation </th></tr>
<tr> <td colspan=1 rowspan=1 > Nebraska (1) </td><td class="highlighted"  colspan=1 rowspan=1 > Edward Zorinsky (D) </td><td class="highlighted"  colspan=1 rowspan=1 > Died March 6, 1987. Successor was appointed to finish the term. </td><td class="highlighted"  colspan=1 rowspan=1 > David Karnes (R) </td><td class="highlighted"  colspan=1 rowspan=1 > March 11, 1987 </td></tr>
<tr> <td colspan=1 rowspan=1 > Nebraska (1) </td><td class="highlighted"  colspan=1 rowspan=1 > David Karnes (R) </td><td class="highlighted"  colspan=1 rowspan=1 > Lost election and resigned November 8, 1988. </td><td colspan=2 rowspan=1 > Vacant to the end of this Congress. </td></tr>
</table>
Question:
How long did Edward Zorinsky serve in the senate before Karnes took over?
Answer:
Edward Zorinsky (D) served in the Senate until March 6, 1987, a seat which was later served by David Karnes (R) from March 11, 1987 until November 8, 1988.