What could cause a noticeable delay in brake application at the rearmost trailer compared to the tractor in a triples combination?

Pick an answer

1. Brakes on every unit always apply at exactly the same instant with no possible delay whatsoever regardless of how far it sits from the tractor
2. Air has to travel through more connections and distance to reach the last unit, which can introduce a slight lag
3. Delay only happens if the rearmost trailer is empty
4. Delay is caused only by tire pressure differences, never by air line length

Correct!

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