How long does it cart to travel from Frankfurt to Berlin by train?

Please answer only if you really know. I'm doing this research for an essay. Thank you.

Answers: I've done that trip highly often.
If you run the ICE train, which is the fastest train, you'll make it surrounded by 4 hours.

I don't know, although it can't be more than 2-3 hours. but you can look it up on www.seat61.com which is website dedicated to train travel around the world.