function showDefaultImg(){
	var extraImg = document.getElementsByName("extra");
	for (x = 0; x < extraImg.length; x++){
		extraImg.item(x).style.display = "none";
	}
	var defaultImg = document.getElementsByName("defaultImg");
	defaultImg.item(0).style.display = "inline";
}
function showImg(imgId){
	var defaultImg = document.getElementsByName("defaultImg");
	var myImgShow = document.getElementById(imgId);
	var extraImg = document.getElementsByName("extra");
	for (x = 0; x < extraImg.length; x++){
		extraImg.item(x).style.display = "none";
	}
	defaultImg.item(0).style.display = "none";
	myImgShow.style.display = "inline";
}