A 60-Kg Object, Initially at Rest in Free Space, "Explodes" into into Three

Multiple Choice

A 6.0-kg object, initially at rest in free space, "explodes" into three segments of equal mass. Two of these segments are observed to be moving with equal speeds of 20 m/s with an angle of 60° between their directions of motion. How much kinetic energy is released in this explosion?

A) 2.4 kJ
B) 2.9 kJ
C) 2.0 kJ
D) 3.4 kJ
E) 1.2 kJ