function my_select_change(vis,id_sel,id_other) {
	my_sel = document.getElementById(id_sel);
	my_other = document.getElementById(id_other);
	index = my_sel.options[my_sel.selectedIndex].value;
	//alert(my_other.style.visibility);
	if(index == vis){
		my_other.style.visibility = 'visible';
	}
	else {
		my_other.style.visibility = 'hidden';
	}
}