function get_anchor() {
	var anchor = self.document.location.hash.substring(1);
	var target_style = document.getElementById(anchor).style;
	target_style.display = 'block';
}

function popdown(ev) {
	
	if (ev == null) { ev = window.event };
	var source_id = (ev.target) ? ev.target.id : ev.srcElement.id;
	var target_elem = source_id;
	target_elem = target_elem.replace('q_', 'a_');
	var target_style = document.getElementById(target_elem).style;
	
	// first hide all existing popdowns, 
	// except for the target div from above
	var divs = document.getElementsByTagName('div');
	
	for ( var i = 0; i < divs.length; i++ ) {
		
		if (/popdown/.test(divs[i].className)) {
			if (divs[i].id != target_elem) {
				divs[i].style.display = 'none';
			}
		}
	}
	
	// then show currently selected popdown
	if (target_style.display != 'block') {
		target_style.display = 'block';
	}
	else {
		target_style.display = 'none';
	}
	
	
	
	return false;
}