function show_hole($num){
   $card=document.getElementById('hiddencard'+$num);
   if(!$card)return false;
   $tip=document.getElementById('courseinstructions');
   $tip.style.display='none';
   $card.style.display='block';
}
function hide_hole($num){
   $card=document.getElementById('hiddencard'+$num);
   if(!$card)return false;
   $card.style.display='none';
}
function show_details($num){
   $details=document.getElementById('hiddendetails'+$num);
   if(!$details)return false;
   $hidden=elements_with_class(document,"*",'hiddendetails');
	 for($i=0;$i<$hidden.length;$i++){
	    $hidden[$i].style.display='none';
	 }
   $details.style.display='block';
}