About Towing a trailer or caravan: 90 km/u is never 'just always': which statement is correct?
On an autoweg or motorway the 90 km/u applies to every trailer, regardless of the permitted maximum mass.
With a trailer or caravan you may always drive at most 90 km/u, even on the motorway, regardless of the weight.
The 90 km/u is explicitly tied to 'autowegen and autosnelwegen'.
A brommobiel may drive faster within the built-up area than outside it, just like an ordinary car.
Explanation
trap: road-type blurring. Book p.119 - the 90 km/u is explicitly tied to 'autowegen and autosnelwegen'. On an ordinary road outside the built-up area (no autoweg sign) 80 km/u simply applies with a trailer