Statements:
No cabin is a room.
All rooms are houses.
No house is a flat.
Some flats are apartments.
Conclusions:
I. Some flats are not rooms.
II. Some apartments may be rooms.
III. All flats being house is a possibility.
All rooms are houses. (A) + No house is a flat. (E) = No room is a flat. (E) ⇒ conversion ⇒ Some flats are not rooms(O). Hence, conclusion I follows. All rooms are houses. (A) + No house is a flat. (E) = No room is a flat. (E) + Some flats are apartments. (I) ⇒ Some apartments are not rooms. (O) ⇒ probable conclusion ⇒ Some apartments may be rooms. (I) Hence, conclusion II follows. No house is a flat. (E) ⇒ conversion ⇒ Some flats are not houses. (O) ⇒ probable conclusion ⇒ Some flats may be houses. (I) Hence, conclusion III does not follows.