function On(obj,obj2)
 {
  mouseOn(obj);
  mouseOn(obj2);
 }
function Off(obj,obj2)
 {
  mouseOff(obj);
  mouseOff(obj2);
 }
function mouseOn(obj)
 {
  document.getElementById(obj).style.visibility = "visible";
 }
function mouseOff(obj)
 {
  document.getElementById(obj).style.visibility = "hidden";
 }