app/views/students/listen.html.erb
<section class="container">
<h1>Listen to Audio</h1>
<% unless @listen.empty? %>
<%= audio_tag(src = @listen, autoplay: false, controls: true, :id => "audio_available")%>
<% else %>
<p>Sorry, no content has been uploaded for today.</p>
<%end%>
</section>