In an action movie, a spy is lying still on top of a train. The train is moving at a speed of 95 km/h. Three bad guys are after the spy. One is in a helicopter flying above the train and moving at the same speed in the same direction as the train. The second is a spotter sitting above a tunnel opening that the train is headed for. The third is in a car that is driving alongside the train, in the opposite direction, at a speed of 105 km/h.
Answer
A
The person in the car and the spotter above the tunnel will both observe the speed of the person on the train as 95 km/h.
B
The person in the helicopter and the spotter above the tunnel will both observe the speed of the person on the train as 95 km/h.
C
The spotter above the tunnel will observe the speed of the spy as 95 km/h, and the person in the car will observe the speed of the spy as 200 km/h.
D
The person in the helicopter will observe the speed of the spy as 95 km/h, and the person in the car will observe the speed of the spy as 105 km/h.