show and hide keep open through query string

with the example below I was wondering if I pass the id below to a querystring how can my javascript read it and keep open

/******************* html example *//////////////////////////
<a href=javascript:showhide('AIR_FRESHENERS','AIR_FRESHENERS_Image','../images/');><img src='..\images\expand.gif' border=0 id='AIR_FRESHENERS_Image'></a><a name='A'>&nbsp;&nbsp;AIR_FRESHENERS</a></td>
      </tr><tr id="AIR_FRESHENERS" style="display:none;">





/************ Javascript *******************************\
function showhide(which,img,imgsrc) {
location.pathname;

      if(document.all && !document.getElementById) {
            document.getElementById = function(id) {
                   return document.all[id];
            }
      }
      if (document.getElementById){
            oWhich = document.getElementById(which).style;
            oImage = document.getElementById(img);
      } else {
            if (document.layers) {
                  oWhich = document.layers[which];
                  oImage = document.layers[img];
            }
      }