function showhide (iwhat,iplusminus)

{
var lwhat = document.getElementById(iwhat); // defines what is shown or hidden according to id reference in tag
var lshow = (lwhat.style.display == 'none'); // removes what is shown from view
lwhat.style.display = (lshow) ? '' : 'none'; // swaps plus and minus
var lsrc = iplusminus.src; // defines new image source according to reference in tag
iplusminus.src = (lshow) ? lsrc.replace ('plus','minus') : lsrc.replace ('minus','plus') // if paragraph is hidden, replaces minus image with plus image, and vice-versa
}