Bad Qubits — Learn Quantum by Doing

Multiple choice

For two spin-1/2 particles, how do the coupled spin states behave under exchange (the swap operator P_12)?

All four coupled states are symmetric under exchange
The triplet is antisymmetric and the singlet is symmetric
All four coupled states are antisymmetric under exchange
The three triplet states (s = 1) are symmetric (eigenvalue +1) and the singlet (s = 0) is antisymmetric (eigenvalue -1)