A vessel at rest at origin of an x-y coordinate system explodes to three pieces. Just after the explosion, one piece, of having mass m, moves with the velocity v in the negative x direction, and a second piece, as well of mass m, moves with the similar velocity in the negative y direction. The third piece consists of mass 3m. Just after the explosion, (i) Determine the magnitude of the velocity of third piece in terms of the given variables? (ii) Find the direction of its motion (as an angle relative to the positive x-axis)?