Why does the following code not display a Billing System application window?

public class MyMenuFx extends Application {

 @Override public void start(Stage applicationStage) { Scene scene = null; Pane pane = null; TextField totalBill = null; pane = new Pane(); scene = new Scene(pane); totalBill = new TextField(); totalBill.setText("The cost of the dish is $10 and for 5 the bill will be $50"); pane.getChildren().add(totalBill); applicationStage.setScene(scene); applicationStage.setTitle("Billing System"); } public static void main(String [] args) { launch(args); } } 

Question 3 options:

	scene.show(); is missing in the start() method
	scene.show(); is missing in the main() method
	applicationStage.show(); is missing in the start() method
	applicationStage.show(); is missing in the main() method