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:
KXOF-CD
Table title:
Digital programming
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Channel </th><th colspan=1 rowspan=1 > Video </th><th colspan=1 rowspan=1 > Aspect </th><th colspan=1 rowspan=1 > PSIP short name </th><th colspan=1 rowspan=1 > Programming </th></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > 31.1 </td><td colspan=1 rowspan=1 > 480i </td><td colspan=1 rowspan=1 > 4:3 </td><td class="highlighted"  colspan=1 rowspan=1 > KXOF-CD </td><td colspan=1 rowspan=1 > Main KXOF-CD programming / UniMás </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > 31.2 </td><td class="highlighted"  colspan=1 rowspan=1 > 720p </td><td colspan=1 rowspan=1 > 16:9 </td><td colspan=1 rowspan=1 > KETF </td><td class="highlighted"  colspan=1 rowspan=1 > Simulcast of KETF-CD </td></tr>
<tr> <td colspan=1 rowspan=1 > 31.3 </td><td colspan=1 rowspan=2 > 480i </td><td colspan=1 rowspan=2 > 4:3 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 > Laff </td></tr>
<tr> <td colspan=1 rowspan=1 > 31.4 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 > Grit </td></tr>
</table>
Question:
What channels did KXOF-CD and KETF-CD begin broadcasting on?
Answer:
KXOF-CD began broadcasting on channel 31.1 and KETF-CD with 720p programming on sub-channel 31.2.