Update '12/player2.js'

12/player2.js

@@ -1,5 +1,5 @@
-var track = document.querySelector("track_2"), 
+var track = document.querySelector("track"), 
-	track_div = document.getElementById("track_2");
+	track_div = document.getElementById("track");
 track.addEventListener('cuechange', function () {
   let cues = track.track.activeCues;  // array of current cues
   console.log("cuechange", cues, cues[0].text, cues[0].startTime, cues[0].endTime);