See below the animation for the correct Actionscript 3.0 code
Frame #1 of actions layer and Frame #100 of actions layer

// This code is in Frame #1 of the layer named "actions" in honor
//                          of ActionScript 3.0, the language for 
//                          programming Flash CS3.

var link:URLRequest = new URLRequest("http://www.uni.edu");
  
skip_btn.addEventListener(MouseEvent.CLICK, onClick);
 
function onClick(event:MouseEvent):void
{
    stop();
    navigateToURL(link, "_self" );
}

// This ActionScript 3.0 programming language code is in frame #100
// of the actions layer of the Flash application.

var link2:URLRequest = new URLRequest("http://www.uni.edu");
   
stop();
navigateToURL(link2, "_self" );