function sichtbarmachen(s){
	var e = document.getElementById(s);
	e.style.visibility = "visible";
}
function verschwinden(s){
	var e = document.getElementById(s);
	e.style.visibility = "hidden";
}
function erscheinen(s){
	var e = document.getElementById(s);
	if(e.style.display == "none"){
		e.style.display = "block";
	}
	else {
		verstecken(s);
	}
}
function verstecken(s){
	var e = document.getElementById(s);
	e.style.display = "none";
}