Which of the following situations will lead to a Doppler shift being observed by a participant of the situation? Question 30 options: A man riding on a horse shouts to a man on a train moving at the same speed and in the same direction as the horse. A police car sits in a parking lot with its lights and sirens on as a crowd stands around and watches. A woman in a speed boat races full throttle away from the dock, where a radio is playing rock and roll. None of the above cases will produce a Doppler shift