function HighLight(i) {
        if (document.images) {
                var thang = document.images[i].src
                var off = thang.lastIndexOf("nr")
                if (off != -1) {
                        document.images[i].src = thang.substring(0,off) + "lt" + ".gif"
                }
        }
}

function Lightsoff(i) {
        if (document.images) {
                var thang = document.images[i].src
                var on = thang.lastIndexOf("lt")
                if (on != -1) {
                        document.images[i].src = thang.substring(0,on) + "nr" + ".gif"                }
        }
}