title: open a new text field on selection of any of last 3 checkbox in a Drop Down Multiple Checkbox
body: <p>What I am trying to do here is when any of the last 3 checkbox is selected in this multiple selection dropdown list, I want to display another <strong>text field</strong> which will be the address field. 
  What I am doing currently is on a selection of a <strong>Information required</strong> checkbox a drop down list is shown as follows:</p>
  
  <p>Any help will be appreciated. Thanks!   </p>
  
  <pre><code>&lt;p id="formSpacing"&gt;
    &lt;input id="inforequired" type="checkbox" value="1" 
           onclick="unhide('hidden-input', this)"&gt;
    &lt;label for="inforequired" class="iconic link"&gt; Information requested&lt;/label&gt;
    &lt;div id="hidden-input" style="display:none"&gt;
  
    &lt;select title="Information Requested" multiple="multiple" 
            name="infoRequested" size="5"&gt;
        &lt;option value="option1"&gt;options1&lt;/option&gt;
        &lt;option value="option2"&gt;options2&lt;/option&gt;
        &lt;option value="option3"&gt;options3&lt;/option&gt;
        &lt;option value="option4"&gt;options4&lt;/option&gt;
        &lt;option value="option5"&gt;options5&lt;/option&gt;
        &lt;option value="option6"&gt;options6&lt;/option&gt;
        &lt;option value="option7"&gt;options7&lt;/option&gt;
        &lt;option value="option8"&gt;options8&lt;/option&gt;
        &lt;option value="option9"&gt;options9&lt;/option&gt;
        &lt;option value="option10"&gt;options10&lt;/option&gt;
    &lt;/select&gt;
  
    &lt;/div&gt;
  &lt;/p&gt;
  </code></pre>