stats.html.erb

Add table head 
<th>Action</th>

Add Send reminder link on the table data

<% if (sub && sub.answer_count || 0 ) < no_qn  %>
                <td> <%= button_to "Send Reminder", {action: 'reminder', user_id: std.user_id}, class:'btn info', data:{ confirm: 'Are you sure you want to send reminder?', disable_with: 'Loading..' }  %>  </td>
            
            <% end %>