var img_expand = new Image();
img_expand.src = "images/plus.jpg";
var img_collapse = new Image();
img_collapse.src = "images/minus.jpg";


function expandHide(a)
{
content=document.getElementById("content"+a);
button=document.getElementById("button"+a);
if(content.style.display == "none" || content.style.display=="") {
		content.style.display = "block";
 		button.src = img_collapse.src;
	}

	else {
		content.style.display = "none";
		button.src = img_expand.src;
	}
}