String str1,str2; @Overridepublicvoidstart(Stage stage){ HBox hbTop=newHBox(); HBox hbBottom=newHBox(); hbBottom.setAlignment(Pos.CENTER); hbBottom.setSpacing(60); VBox vbox=newVBox(); vbox.setSpacing(15); Text t1=newText("Number1:"); t1.setFont(newFont(20)); Text t2=newText("...