When securing a passenger traveling in a wheelchair in a designated wheelchair bay on a bus, what must be ensured?

1. The wheelchair must be positioned against the padded backrest or secured with approved restraint belts, and wheelchair brakes must be locked
2. The wheelchair user must face sideways with free-rolling wheels
3. Wheelchairs must always be folded and stowed in the luggage hold while the passenger sits on the floor
4. No securing is required if the bus travels below 50 km/h