Connected warrens - tunnels
Reasoning
Tunnels between warrens could be represented using graphs and represented by an adjacency matrix. This could apply some of the theory content of unit 1. The adjacency matrix will have a 0 if the 2 warrens aren't connected and a 1 if they are. It could be used to move rabbits from one warren to another if their warren is attacked. It could also be used to show which locations are linked in the landscape