function hide(obj){
document.getElementById(obj).style.display = 'none';
}
	
function show(obj){
document.getElementById(obj).style.display = '';
}
	
	
function toggle_visibility(id) {
var e = document.getElementById(id);
if(e.style.display == 'block')
e.style.display = 'none';
else
e.style.display = 'block';
}