Two billiard balls move at right angles and meet at the origin. Ball A (the cue ball, 175 g) is initially moving upward along the y axis at vA = 2.0 m/s, and ball B (a numbered ball, 155 g) is moving to the right along the x axis at vB = 3.7 m/s. After the collision, ball B is moving along the positive y axis at 2.85 m/s.
What is the final velocity & direction of Ball A?