function roll_over(img_name, img_src){
	document[img_name].src = img_src;
}

function switchit(id){ 
	var dStyle=document.getElementById(id).style;

	if (dStyle.display=="none"){ 
		dStyle.display="block";
		roll_over("i"+id, "images/less.png");
		
	}
	else{ 
		dStyle.display="none";
		roll_over("i"+id, "images/more.png");
	}
}