IntroExercise7/Answer

Status?  

If white plays first, the shape lives easily with three eyes, one more than necessary.

Status?  

If black plays first at , the shape is dead. Later, he can follow with and , which threatens to capture. If white captures the stones with :

Status?  

It becomes the straight three, and black kills with .

Status?  

Any attempt by white to interrupt only makes things worse. If white plays here, the shape is the bent three, and the stones are dead.