answer: #Person2# let #Person1# wait for 20 minutes before the tour.
documents: #Person1#: Excuse me, driver, you have kept us waiting for 15 minutes. Can't we start the tour right now?
  #Person2#: I am sorry, sir, there are still 5 minutes remaining. . . OK, it's time. We will take a roll call before starting the fantasy sightseeing.
  #Person1#: Finally. How long does the tour last?
  #Person2#: For about 3 hours. Enjoy your trip.