if (document.images) {
a004_off = new Image(); a004_off.src = "a004.gif"
a004_over = new Image(); a004_over.src = "a004_over.gif"
}
function turn_off(ImageId) {
  if (document.images != null) {
    document[ImageId].src = eval(ImageId + "_off.src");
  }
}
function turn_over(ImageId) {
  if (document.images != null) {
    document[ImageId].src = eval(ImageId + "_over.src");
  }
}