"The quiz for this lesson is an easy life-and-death problem."
(;AW[cd]AW[cc]AW[dc]AW[be]AW[bf]AW[bg]AW[df]AW[ef]AW[ff]AW[gf]AB[ce]AB[de]AB[dd]AB[fd]AB[fe]AB[ec]AB[gc]AB[hc]AW[ic]AW[ib]AW[hd]AW[gd]AW[if]AB[bd]C[Black to live without ko.]AP[goproblems]
(;B[bc];W[bb]
(;B[db];W[cb];B[fb];W[da]
(;B[ee];W[eb])
(;B[ea];W[eb]))
(;B[cb];W[db];B[ba];W[ca];B[ab]))
(;B[db];W[cb];B[fb];W[da];B[ea];W[eb])
(;B[fb];W[db];B[ee];W[eb];B[hb];W[ga])
(;B[ee];W[eb];B[fb];W[db];B[hb];W[ga])
(;B[bb];W[bc];B[db];W[cb];B[ca];W[ad];B[fb]C[RIGHT]))