You are on a train traveling east at speed of 28.0 m/s with respect to the ground.
1) If you walk east toward the front of the train, with a speed of 1.2 m/s with respect to the train, what is your velocity with respect to the ground?
2) If you walk west toward the back of the train, with a speed of 1.8 m/s with respect to the train, what is your velocity with respect to the ground?
3) Your friend is sitting on another train traveling west at 18.0 m/s. As you walk toward the back of your train at 1.8 m/s, what is your velocity with respect to your friend?