(;AB[fa]AB[fb]AB[ec]AB[ed]AB[fd]AB[gd]AB[hd]AB[hc]AB[ic]AB[jc]AB[jb]AB[ja]AW[ea]AW[eb]AW[db]AW[dc]AW[dd]AW[ee]AW[fe]AW[ge]AW[he]AW[id]AW[jd]AW[kd]AW[kc]AW[kb]AW[ka]AW[hb]AP[goproblems]
(;W[gb];B[fc]LB[ie:T]C[Click T if wish to tenuki.]
(;W[ib]LB[aa:T];B[aa]C[Now demonstrate why black is dead.]
(;W[ga];B[ia]C[CHOICE];W[ha]C[RIGHT];B[gc];W[hb]C[RIGHT])
(;W[ha]C[Seki. White killed his potential eye at H19. If white tries to fill, there are six non-rabbity six points left.])
(;W[ia]LB[ab:T]C[RIGHT]
(;B[ga]C[Now demonstrate the move that kills black quickest.CHOICE];W[ha];B[gc];W[hb]C[RIGHT])
(;B[ab]C[CHOICE]
(;W[ga]C[Creating an eye is correct.RIGHT])
(;W[gc]C[Seki])
(;W[ha]C[Seki])))
(;W[gc]C[Seki. White could have killed black. White can't form an eye without dying and can't form a dead shape. If white fills, black has non-rabbity six points after capturing white.]))
(;W[ie];B[ha]C[]
(;W[ib]
(;B[ga]C[Seki])
(;B[ia]C[Seki. White has a ko threat.]))
(;W[ga]C[];B[ib]C[White can only approach with Wj19 ko.])
(;W[ia];B[ib])
(;W[gc];B[ib]C[Black is alive because white can't push at wG19.]))
(;W[ga]C[Black can't keep white from forming an eye or a bulky five to kill. So black stones are dead.RIGHT])
(;W[ha]LB[aa:T];B[aa]C[Seki. White filled his potential eye at H19. If white tries to fill, a non-rabbity six is formed and black can live. White can form a bulky five to create a ko threat to kill the surrounding stones.])
(;W[ia];B[ga]C[CHOICE]
(;W[ha]C[RIGHT])
(;W[ib]C[RIGHT])
(;W[gc]C[Seki]))
(;W[gc];B[ha]
(;W[ib]C[Seki])
(;W[ia];B[ib]C[Black is alive. White can't push at G19.])))
(;W[fc];B[gb]C[Black can make two eyes with Bg17. White can't push at G17.])
(;W[gc];B[gb]C[Black can connect at F17. White can't push at F17.])
(;W[ga];B[gb]C[Bf17 and Bg17 are miai for life.]TR[fc]TR[gc])
(;W[ha];B[gb]C[Bf17 and Bg17 are miai for life.]TR[fc]TR[gc])
(;W[ia];B[gb]C[Bf17 and Bg17 are miai for life.])
(;W[ib];B[gb]C[bF17 and bg17 are miai for life.]))