Statements : All windows are doors.
All entrances are windows.
No gate is a door.
Conclusions : I. At least some windows are gates.
II. No gate is an entrance.
Explanation:
All entrances are windows (A) + All windows are doors (A) + [No gate is a door (E)] = No door is a gate (E) = A + E = E = No entrance is a gate.
Hence, conclusion II follows .
Again,
All window are doors (A) + [No gate is a door (E)] = No door is a gate (E) = A + E = E = No window is a gate.
Thus, conclusion I does not follow.