var selectedAntw = "";
		function Antwoord(antw){
			var img;
			var imgSrc;
			var newSrc;
			if (selectedAntw != ""){
				img = document.getElementById(selectedAntw);

				if (img == null)
					return false;

				imgSrc =  img.src;
				newSrc = imgSrc.replace(/_yes/,"_no");
				img.src = newSrc;
			}

			img = document.getElementById(antw);
			if (img == null)
				return false;

			imgSrc =  img.src;
			newSrc = imgSrc.replace(/_no/,"_yes");
			img.src = newSrc;
			selectedAntw = antw;
			document.forms[0].antwoord.value = antw;
		}

		function Verstuur(){
			if (document.forms[0].antwoord.value != "")
			{
				document.forms[0].submit();
				return true;
			}else{
				return false;
			}
		}