function getElement(aID)
{return (document.getElementById) ? document.getElementById(aID) : document.all[aID];} 

function showHide(id) 
{
	tr = getElement(id);
	var d;
	if (tr.style.display == '')	{ d	= 'none'; getElement('chang').src="/img/menu_2.gif"; } 
	else { d	= ''; getElement('chang').src="/img/menu_3.gif"; }
	tr.style.display	= d;
	return true;
}