(;FF[4]SZ[19]GM[1]CA[UTF-8]ST[2]C[Problem 1 Black to play]AB[jf][oe][lf][mf][nf][la][jb][lb][jc][lc][jd][oc][qc][je][od]AW[me][ne][kc][mc][nc][kd][ka][ld][kb]PB[ ]
(;B[nd]C[Failure.
Problem 2.];W[ob];B[pb];W[oa];B[mb];W[ma];B[na]
;W[nb]C[Black cannot connect so is dead.])
(;B[oa]C[Correct.
Problem 4.]
(;W[nd]C[Problem 3.];B[ma]C[Correct.])
(;W[na]C[Correct. 
Problem 5];B[nd];W[ob];B[pb];W[pa];B[qa];W[mb]
;B[oa]C[Ko.])))
