A train rolls past a stationary observer. To him, the train is moving at a speec of 23 m/s west

object 2 because all the other ones are wrong

power out to power in less than 100%

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.