A grenade exploded while it was flying through the air! No one was hurt, but it made a loud noise. The grenade burst into three pieces: a 300 g piece that flew north at 30 m/s, a 500 g piece that flew east at 40 m/s, and a 400 g piece that flew [W20S] at 55 m/s. Determine the speed of the grenade before it exploded. What direction was the grenade moving in before the collision