function show_sub(n)
{
var div_name = "teach" + n;
var div_image = "images" + n;
	if (document.all[div_name].style.display == "")
	{
	document.all[div_name].style.display = 'none';
	document.images[div_image].src = "/eng/image/arror_down1.gif";
	}
	else
	{
	document.all[div_name].style.display = '';
	document.images[div_image].src = "/eng/image/arror_down2.gif";
	}
}
function show_teach(n)
{
var div_name = "teach" + n;
var div_image = "images" + n;
	if (document.all[div_name].style.display == "")
	{
	document.all[div_name].style.display = 'none';
	document.images[div_image].src = "/eng/image/increase2.gif";
	}
	else
	{
	document.all[div_name].style.display = '';
	document.images[div_image].src = "/eng/image/decrease2.gif";
	}
}
function mOvr1(src,clrOver) {
    if (!src.contains(event.fromElement)) {
	  src.style.cursor = 'pointer';
	  src.bgColor = clrOver;
	}
  } 
  function mOut1(src,clrIn) {
	if (!src.contains(event.toElement)) {
	  src.style.cursor = 'default';
	  src.bgColor = clrIn;
	}
  }