A 50.0 kg body is moving in the direction of the positive x axis with a speed of 293 m/s when, owing to an internal explosion, it breaks into three pieces. One part, whose mass is 9.9 kg, moves away from the point of explosion with a speed of 481 m/s along the positive y axis. A second fragment, whose mass is 2.6 kg, moves away from the point of explosion with a speed of 450 m/s along the negative x axis. Ignoring the effects of gravity, what is the speed of the third fragment?