In the arrangement of the figure, billiard ball 1 moving at a speed of 2.6 m/s undergoes a glancing collision with identical billiard ball 2 that is at rest. After the collision, ball 2 moves at speed 0.69 m/s, at an angle of θ2 = 30o. What are (a) the magnitude and (b) the direction (angle θ1) of the velocity of ball 1 after the collision?