function populateSelect(elt, value, show )
{ 
    elt.options.length = 0;
  //  elt.options[0] = new Option('', '');
    for (i = 0; i < show.length; i++) {
        elt.options[i] = new Option(show[i], value[i]);
    }
    elt.selectedIndex = 0;
}

  function clearSelect(elt)
{
    elt.options.length = 0;
    elt.selectedIndex = 0;
}

function selectSelect(elt,index)
{
    elt.selectedIndex = index;
    
}