In Example R9 $498 \mathrm{MeV}$ ) Decays to Two Pions (Each with a Mass Of )

True/False

In example R9.4, a kaon (whose mass is $498 \mathrm{MeV}$ ) decays to two pions (each with a mass of $135 \mathrm{MeV}$ ).

-(b) The total system's mass decreases in this process.