Correct answer: Rb51...R:b2 2.Q:b2# 1...Rb4 2.b3# 1...Rb5/Rb6/Rb7/Rb8 2.b3#/b4# 1...Ra3 2.b:a3# 1...Rc3 2.b:c3# 1...Bb5 2.Qa7# 1...Ng3/Nh2/N