A certain thing is thrown twice from a place with the gap of 45 minutes between the two shots. A girl approaching this point in a train heard the second shot 44 minutes after she heard the first shot. What is the speed of train (in kmph) if sound travels at 660 m/s? a) 62 km/hr b) 54 km/hr c) 48 km/hr d) 27 km/hr