Answers

(No. 167: July 5, 1999)

Elementary level: Answer

Black 1 is the vital point. After White 2,
Black plays 3 and White gets a Ko with 4.

Elementary level: Reference Diagram

If White 2, Black kills White with 3 to 5.

Elementary level: Wrong Answer

Black 1 allows White to live with 2 and 4.
(The same shape as the preceding problem)

Intermediate level: Answer

Black 1 is crucial. After White 2,
Black gets a Ko with 3 and 5.

Intermediate level: Wrong Answer

Black 1 is wrong. After White 2 and 4, Black is dead.