
    <!-- function that display on and off specified element -->
	function viewElement(element_id, other_element_id) {
	
	var element = document.getElementById(element_id);
	//var	status = element.getAttribute('checked');
	var status = element.checked;
	if (status == true) { document.getElementById(other_element_id).style.display = 'block'; }
	else { document.getElementById(other_element_id).style.display = 'none'; }
	}