What must you ensure regarding the split brake pedals (Einzelradbremse / geteiltes Bremspedal) before driving a tractor on paved public roads?

1. The pedals must be uncoupled so each rear wheel can be braked separately
2. The two brake pedals must be locked together with the coupling latch (Verriegelungslasche) so both rear wheels brake evenly
3. The pedals must be coupled only when a trailer is attached
4. The pedals must be uncoupled and the differential lock engaged instead