function showTip(imgTip)
{
  if (document.images && document['tip'])
    document['tip'].src = imgTip.src
}

function showArrow(strImgName)
{
  if (document.images)
    document[strImgName].src = imgArrow.src;
}

function showClearDot(strImgName)
{
  if (document.images)
    document[strImgName].src = imgClearDot.src;
}

function showHome()
{
  if (document.images)
    document['home'].src = imgHome.src;
}

function revertHome()
{
  if (document.images)
    document['home'].src = 'http://www.sc.edu/template/images/hdr_usc.gif';
}


// preload rollovers
if (document.images)
{
  var imgArrow = new Image();
  imgArrow.src = 'http://www.sc.edu/template/images/lnav_arrow_white.gif';

  var imgHome = new Image();
  imgHome.src = 'http://www.sc.edu/template/images/hdr_usc_sel.gif';

  var imgClearDot = new Image();
  imgClearDot.src = 'http://www.sc.edu/template/images/dot_clear.gif';
}