(A) Prove or disprove, every subring of a PID is a PID. If you disprove, you need to
justify your counter-example.
(B) Prove or disprove, every subring of a UFD is a UFD. If you disprove, you need to
justify your counter-example.
(A) Prove or disprove, every subring of a PID is a PID. If you disprove, you need to
justify your counter-example.
(B) Prove or disprove, every subring of a UFD is a UFD. If you disprove, you need to
justify your counter-example.