(No. 110: June 1, 1998)
Elementary level: Answer
Black 1 is crucial to live. If White 2, Black
lives with 3. If White 2 at 3, Black lives with 2.
Elementary level: Wrong Answer
Black 1 fails. White 2 is the vital point,
and after White 6, the next diagram.
Elementary level: Wrong Answer (Continued)
After Black 7, White plays 8. Black has no way
to live because it is short of liberties.
Intermediate level: Answer
Black 1 is crucial. After White 4, Black lives
with 5 and 7. If White 4 at 8, Black lives with 4.
If White 6 at 8, Black plays at 6. Taking the four
White stones, part of the Black can survive.
Intermediate level: Wrong Answer
If Black plays 1 first and then 3, Black becomes
short of liberties, and dies with the moves to White 8.