My first problem, hope I covered all variations. Should be fairly easy.
(;AW[ir][jr][kr][mr][nr][or][pr][rr][sr][is][ls][qs][rs]AB[hq][iq][jq][kq][lq][mq][nq][oq][pq][qq][rq][sq][hr][lr][qr][hs]LB[ks:A]
C[White just failed to play at A, assuming he would lose only the 4 stones on the left. Show him otherwise and kill the whole corner.]
(;B[ps]CR[ps]
;W[os]CR[os]
;B[ms]CR[ms]
;W[ns]CR[ns]
;B[ks]CR[ks]C[RIGHT
Well done!])
(;B[ms]CR[ms]
;W[ps]CR[ps]
(;B[ns]CR[ns]
;W[os]CR[os]
;B[ms]CR[ms]
;W[ns]CR[ns]
;B[ks]CR[ks]C[RIGHT
Well done!])
(;B[ks]CR[ks]
;W[ns]CR[ns]))
(;B[ks]CR[ks]
;W[ms]CR[ms]
;B[ps]CR[ps]
;W[os]CR[os])
(;B[js]CR[js]
;W[ks]CR[ks])
(;B[ns]CR[ns]
;W[ks]CR[ks])
(;B[os]CR[os]
;W[ks]CR[ks]))