function toggleLayer(whichLayer) {		
if (document.getElementById) {
	// this is the way the standards work
	var style2 = document.getElementById(whichLayer).style;
	if (style2.display=="block") style2.display = "none";
	else style2.display = "block";
	//style2.display = style2.display? "":"block";
}
else
	if (document.all) {
		// this is the way old msie versions work
		var style2 = document.all[whichLayer].style;
		if (style2.display=="block") style2.display = "none";
		else style2.display = "block";
		//style2.display = style2.display? "":"block";
	}
	else
		if (document.layers) {
			// this is the way nn4 works
			var style2 = document.layers[whichLayer].style;
			if (style2.display=="block") style2.display = "none";
			else style2.display = "block";
			//style2.display = style2.display? "":"block";
		}
}