Correct answer: Nb11.Nd1?? (2.Rb1#/R2b3#/R2b4#/R2b5#/R2b6#/R2b7#/Rc2#/Rd2#/Re2#/Rf2#/Rg2#/R:h2#) 1...Rg1 2.Rg2# 1...Re1 2.R