function open_menu(id)
{
	document.getElementById('menu_td'+id).style.display= '';
}

function close_menu(id)
{
	document.getElementById('menu_td'+id).style.display='none';
}

function open_letters_menu(id)
{
	document.getElementById('menu_letters_td'+id).style.display= '';
}

function close_letters_menu(id)
{
	document.getElementById('menu_letters_td'+id).style.display='none';
}