Solution to help-mate number 1

The theme in each of the solutions is that of self-blocks by the black rook.

Part (a) diagram

Black moving first 1. Rb7 Kd6 2. Kc8 Rg8 mate.

Part (b) diagram plus white bishop on f8

Black moving first 1. Ka8 Bc5 2. Rb8 Ra7 mate.

Part (c) diagram plus white knight on e8.

Black moving first 1. Ra6 Nd6 2. Ra8 Rb7 mate.