Aboy of mass 60 kg stands on a boat of mass 250 kg. this system is stationary. from the boat, the boy throws a rock of mass 1 kg into the water with a velocity of 10 m/s. what is the magnitude and direction of the boat's motion as a result of this? a) the boat moves in the direction of the rock with a velocity of 31 m/s. b) the boat moves in the direction of the rock with a velocity of 0.02 m/s. c) the boat moves in a direction opposite to the rock with a velocity of 0.03 m/s d) the boat moves in a direction opposite to the rock with a velocity of 10.1 m/s.