H1gan: Problem is not Easy. Solved the entire set with 5 second's average. This gives off a tombstone vibe and is how I played it out after failing it two or three different times before realizing that it's just a liberty management problem.
DGM: An update to my prior comment, the admin didn't explain why it didn't work, but here's the flaw in my sequence. After W-F2, responding B-D1 necessitates W-E1. Then B-E5 forces W-E6. Finally, B-C4 captures the two white stones and black lives.
caranthir: You're right, except I think with W E1 you mean W F1.
DGM: There's another sequence that captures but counts as a loss. When oriented on the bottom left of the board, white to capture: W-D5, B-E2, W-F3, B-C2, W-F2.
At this point black could respond D1 or E1; white captures with F1. Or black could try F1; white captures with F1.
Ischemgeek : After w Atari the second line cutting stone, b can either descend with the O4 group or the Q2 group and both successfully capture as the S3 group doesn't suffer from a shortage of liberties.
There is a provocative proverb saying "if you can count up to two then you are a dan player". I think this tsumego illustrates this feeling :)