Can someone help me with a physics problem?

I am having trouble figuring this problem out. It says: The electric motor of a model train accelerates the train from rest to .620 m/s in 21ms. The total m of the train is 875g. Find the average power delivered to the train during acceleration. It maybe a typo error in my textbook or maybe I am reading it wrong but 21.0 ms is that microseconds?