function addOption(selectId, txt, val)
{
    var objOption = new Option(txt, val);
    document.getElementById(selectId).options.add(objOption);
}

function showHide(id){
	if (document.getElementById && document.getElementById(id)){
		if (document.getElementById(id).style.visibility == "visible"
			|| document.getElementById(id).style.display == "block"){
			// hide it
			document.getElementById(id).style.visibility = "hidden";
			document.getElementById(id).style.display = "none";
		}else{
			// show it
			document.getElementById(id).style.visibility = "visible";
			document.getElementById(id).style.display = "block";
		}                      
	}
}

function ChangeImage(imgId, newSrc, id){	
	document.getElementById(imgId).src=newSrc;
	document.getElementById(imgId).className=id;
}