if (top == self) self.location.href="index.html";
function getTagById (tagId) {
   var selectedTag;
   if (document.all) {
      selectedTag = document.all.item(tagId);
   } else {
      selectedTag = document.getElementById(tagId);
   }
   return selectedTag;
}

function displayDropDownMenu(divId, imgId, imgLocSel, imgLocUnSel) {
   var tagToSwitch = getTagById(divId);
   var imgToSwitch = getTagById(imgId);
   if (tagToSwitch.style.display == "" || tagToSwitch.style.display == "none") {
      tagToSwitch.style.display = "block";
      imgToSwitch.src = imgLocSel;
      if (document.all) {
         tagToSwitch.scrollIntoView();
      }
   } else {
      tagToSwitch.style.display = "none";
      imgToSwitch.src = imgLocUnSel;
   }
}   
function switchImage(imgId, imgLoc) {
   var imgToSwitch = getTagById(imgId);
   imgToSwitch.src = imgLoc;
}