function swap(ref, filename)
{
	if(window.document.images) {
		window.document.images[ref].src = filename;
	}
}

function openWindow(theURL, winName, features) { 
	window.open(theURL, winName, features);
}

function chooseRandom(myarray) {
	var numElements = myarray.length;
	var chosen = Math.floor( Math.random()*(numElements) );
	return myarray[chosen]; 
}