A player bounces a 0.45 kg soccer ball off her head, changing the velocity of the ball from vector v i = (8.6 m/s)x + (-2.1 m/s)y to vector v f =(5.8 m/s)x + (3.4 m/s)y hat. The ball is in contact with the player's head for 6.7ms.
What is the magnitude of the impulse delivered to the ball?