void Start()
        {
            // hide the restart button
            restartButton.SetActive(false);

            // show the rockets
            gameController.PlaceRocketsOnScreenSideBySide();

            // update the performance metrics
            gameController.UpdatePerformanceMetrics(true);

            // send robot utterance that the round is over and try to find one mistake to highlight
            gameController.SendRobotUtterance("round-over", false);
            mistakeMadePiecePair    = gameController.FindOneMistakeBetweenRockets();
            feedbackUtteranceToMake = DetermineFeedbackToGive(mistakeMadePiecePair);

            // display the appropriate text in the tutorial button
            if (gameController.tutorialMode == Constants.TUTORIAL_ON)
            {
                tutorialButton.SetActive(true);
            }
            else if (gameController.tutorialMode == Constants.TUTORIAL_OFF)
            {
                tutorialButton.SetActive(false);
            }

            // initialize the timing variables
            secondsElapsed = 0;
            timeElapsed    = 0f;
        }