// JavaScript Document

//normal_image = new Image();
//normal_image.src = "images/menuprinc/rosio1.jpg";

function preCarga() {
	//if (!document.images) return;
		var ar = new Array();
		var arguments = preCarga.arguments;
		for (var i = 0; i < arguments.length; i++) {
			ar[i] = new Image();
			ar[i].src = arguments[i];
		}
}

<!-- repeat the 4 lines above for any subsequent images. -->

function swap(elid,nuevaimg){
	document[elid].src=nuevaimg;
}

function show_it(menushow){
		document.getElementById(menushow).style.visibility='visible';

}
	
function hide_it(menushow){
	document.getElementById(menushow).style.visibility = "hidden";
	//document.getElementById(menushow).style.display = "none";
}

//preCarga();