function show(anId)
{
  node = document.getElementById(anId);
    
  if (node.style.display == "none")
  {
    node.style.display = "block";
    node.style.height = "auto";
  }
  else
  {
    node.style.display = "none";
    node.style.height = "0";
  }
  node = document.getElementById(anId + "Img");
  if (node.src==i1.src)
  {
    node.src=i2.src;
  }
  else
  {
    node.src=i1.src;
  }
}