Atrain of mass 1.2 x 10 kg, starts from rest and gets to a maximum speed of 20 mi/h in 6.0 minutes, having a constant acceleration during that time. ignoring the air dr orce and friction, and assuming that throughout the motion it stays at the same altitude, what is the required power of its engine? 30 mw 6.0 mw 15 mw 30 mw