Netemul where did I make a mistake?

Question

Computer networks

Help to find an error in building this network. Can't send packets from PC1 to PC6

Answer 1

With masks and addressing everything is all right.
In my opinion, the route on R1 for 172.23.73.0/24 should be registered for the interface 91.122.40.2.
In reality, usually, the interface is not explicitly set for the route, it is calculated by itself from the gateway address.