function show(id) {
	document.getElementById(id).style.visibility = "visible";
}

function hide(id) {
	document.getElementById(id).style.visibility = "hidden";
}

var baseRef = "";
var type = "png";

function over(id){
document.images[id].src = eval("'" + baseRef + id + "_ov." + type + "'");
}

function out(id){
document.images[id].src = eval("'" + baseRef + id + "." + type + "'");
}