A heavy nucleus \( N \), at rest, undergoes fission \( N \rightarrow P + Q \), where \( P \) and \( Q \) are two lighter nuclei. Let \( \delta = M_{N} - M_{P} - M_{Q} \), where \( M_{P}, M_{Q} \) and \( M_{N} \) are the masses of \( P, Q \) and \( N \), respectively. \( E_{P} \) and \( E_{Q} \) are the kinetic energies of \( P \) and \( Q \), respectively. The speeds of \( P \) and \( Q \) are \( v_{P} \) and \( v_{Q} \), respectively. If \( c \) is the speed of light, which of the following statement(s) is (are) correct?
