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:
Mark Garner
Table title:
Achievements
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Year </th><th colspan=1 rowspan=1 > Competition </th><th colspan=1 rowspan=1 > Venue </th><th colspan=1 rowspan=1 > Position </th><th colspan=1 rowspan=1 > Event </th><th colspan=1 rowspan=1 > Notes </th></tr>
<tr> <th colspan=6 rowspan=1 > Representing Australia </th></tr>
<tr> <td colspan=1 rowspan=3 > 1986 </td><td colspan=1 rowspan=3 > World Junior Championships </td><td colspan=1 rowspan=3 > Athens, Greece </td><td colspan=1 rowspan=1 > 8th (sf) </td><td colspan=1 rowspan=1 > 200m </td><td colspan=1 rowspan=1 > 21.42 (wind: -0.6 m/s) </td></tr>
<tr> <td colspan=1 rowspan=1 > 10th (h) </td><td colspan=1 rowspan=1 > 4 × 100 m relay </td><td colspan=1 rowspan=1 > 40.56 </td></tr>
<tr> <td colspan=1 rowspan=1 > 9th (h) </td><td colspan=1 rowspan=1 > 4 × 400 m relay </td><td colspan=1 rowspan=1 > 3:09.65 </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=5 > 1988 </td><td class="highlighted"  colspan=1 rowspan=3 > World Junior Championships </td><td colspan=1 rowspan=3 > Sudbury, Canada </td><td colspan=1 rowspan=1 > 9th (sf) </td><td colspan=1 rowspan=1 > 200m </td><td colspan=1 rowspan=1 > 21.21 (wind: +2.0 m/s) </td></tr>
<tr> <td colspan=1 rowspan=1 > 10th (h) </td><td colspan=1 rowspan=1 > 4 × 100 m relay </td><td colspan=1 rowspan=1 > 40.67 </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > 2nd </td><td class="highlighted"  colspan=1 rowspan=1 > 4 × 400 m relay </td><td colspan=1 rowspan=1 > 3:07.60 </td></tr>
<tr> <td colspan=1 rowspan=2 > Olympic Games </td><td colspan=1 rowspan=2 > Seoul, South Korea </td><td colspan=1 rowspan=1 > 26th (qf) </td><td colspan=1 rowspan=1 > 200m </td><td colspan=1 rowspan=1 > 21.08 </td></tr>
<tr> <td colspan=1 rowspan=1 > 6th </td><td colspan=1 rowspan=1 > 4 × 400 m </td><td colspan=1 rowspan=1 > 3:02.49 </td></tr>
<tr> <td colspan=1 rowspan=2 > 1989 </td><td colspan=1 rowspan=2 > World Cup </td><td colspan=1 rowspan=2 > Barcelona, Spain </td><td colspan=1 rowspan=1 > 8th </td><td colspan=1 rowspan=1 > 400 m </td><td colspan=1 rowspan=1 > 46.081 </td></tr>
<tr> <td colspan=1 rowspan=1 > 7th </td><td colspan=1 rowspan=1 > 4×400 m relay </td><td colspan=1 rowspan=1 > 3:04.881 </td></tr>
<tr> <td colspan=1 rowspan=2 > 1990 </td><td colspan=1 rowspan=2 > Commonwealth Games </td><td colspan=1 rowspan=2 > Auckland, New Zealand </td><td colspan=1 rowspan=1 > 6th </td><td colspan=1 rowspan=1 > 400m </td><td colspan=1 rowspan=1 > 46.10 </td></tr>
<tr> <td colspan=1 rowspan=1 > – </td><td colspan=1 rowspan=1 > 4 × 400 m </td><td colspan=1 rowspan=1 > DQ </td></tr>
<tr> <td colspan=1 rowspan=3 > 1991 </td><td colspan=1 rowspan=2 > World Indoor Championships </td><td colspan=1 rowspan=2 > Seville, Spain </td><td colspan=1 rowspan=1 > 8th (sf) </td><td colspan=1 rowspan=1 > 400m </td><td colspan=1 rowspan=1 > 47.06 </td></tr>
<tr> <td colspan=1 rowspan=1 > 4th </td><td colspan=1 rowspan=1 > 4 × 400 m </td><td colspan=1 rowspan=1 > 3:08,49 </td></tr>
<tr> <td colspan=1 rowspan=1 > World Championships </td><td colspan=1 rowspan=1 > Tokyo, Japan </td><td colspan=1 rowspan=1 > 8th </td><td colspan=1 rowspan=1 > 400m </td><td colspan=1 rowspan=1 > 45.47 </td></tr>
<tr> <td colspan=1 rowspan=1 > 1992 </td><td colspan=1 rowspan=1 > Olympic Games </td><td colspan=1 rowspan=1 > Barcelona, Spain </td><td colspan=1 rowspan=1 > 28th </td><td colspan=1 rowspan=1 > 400m (qf) </td><td colspan=1 rowspan=1 > 46.85 </td></tr>
</table>
Question:
Which event did Mark Garner participate in at the 1988 World Junior Championships and which medal did he win? 
Answer:
Mark Garner won the silver medal in the 4 × 400 m relay at the 1988 World Junior Championships.