3. A particle X of mass m at rest in the lab decays into three particles X1,2,3 of masses m 1,2,3. \text { 1. Show that } m_{1}+m_{2}+m_{3} \leq m_{0} 3. If particles X₂ and X3 are the result of the decay of an intermediate particle X' of mass m², i.e., if the process is X → X₁ X' followed by X' → X2 X3, what can you say about E₁? 2. Find upper bounds on the energies E1,2,3 of the final particles.