WebObject and Storyline Variable

Thanks everyone! I was able to use Jean-Guy's version to show a Smartsheet form inside a Storyline object. This is the code that worked for me:

var player = GetPlayer();

//This will work with the first iframe on the slide with the class name of "shown"
var iFrameId = document.getElementsByClassName('shown')[2];
console.log(iFrameId);

var src="https://app.smartsheet.com/b/form/12345";

var score=player.GetVar ("Score");

//Build the smartURL here > var fullurl = src + "?var1=" + value1 + "&var2=" + value2;
var fullurl = src + "?Quiz=" + score;

//Send the new smartURL to the web object
iFrameId.setAttribute('src', fullurl);