Physics question.. A train is going 100 km/h to the right and a rubber ball is thrown at it to the left, at 100 km/h. It bounces back from the front of the train.

1. How fast does a person conducting the train percieve the ball to be travelling?
I think it's 200 km/h, just from pure intuition, but I can't seem to prove it with vectors. In my mind the velocity vectors just cancel each other, see pic.

2. How fast does a bystander (his reference frame is not moving) see the ball bouncing back? My friend says 300 km/h but I don't see where this is coming from.

Also I'm not sure if the ball gains extra momentum from hitting the train.