[jquery] jQuery selector first td of each row

You can do it like this

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$(function(){_x000D_
  $("tr").find("td:eq(0)").css("color","red");_x000D_
})
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<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<table>_x000D_
  <tr>_x000D_
    <td>col_1</td>_x000D_
    <td>col_2</td>_x000D_
  </tr>_x000D_
  <tr>_x000D_
    <td>col_1</td>_x000D_
    <td>col_2</td>_x000D_
  </tr>_x000D_
  <tr>_x000D_
    <td>col_1</td>_x000D_
    <td>col_2</td>_x000D_
  </tr>_x000D_
  <tr>_x000D_
    <td>col_1</td>_x000D_
    <td>col_2</td>_x000D_
  </tr>_x000D_
</table>
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