A 2.97-kg projectile is fired with an initial speed of 133 m/s at an angle of 28° with the horizontal. At the top of its trajectory, the projectile explodes into two fragments of masses 0.97 kg and 2 kg. At 3.87 s after the explosion, the 2-kg fragment lands on the ground directly below the point of explosion. (a) Determine the energy released in the explosion.