Which of the following are correct rules of towing?

(i) Only two people are allowed in the towed vehicle.
(ii) The tow rope may not be shorter than 2 metres.
(iii) Tractors may carry 10 people in a trailer if travelling at 30 km/h or less.
(iv) On the freeway while not exceeding 30 km/h, you may tow a vehicle with a tow rope.