<script type="text/javascript">
 
 function display(action, id)
 {
 if (action == 'show')
 {
 document.getElementById("explanation"+id).style.display = "block";
 document.getElementById("link"+id).href= "javascript:display('hide', "+id+")";
 document.getElementById("link"+id).innerHTML = "Close";
 }
 
 if (action == 'hide')
 {
 document.getElementById("explanation"+id).style.display = "none";
 document.getElementById("link"+id).href= "javascript:display('show', "+id+")";
 document.getElementById("link"+id).innerHTML = "Explain";
 }
 }
 
 </script>