what is the posted speed
The first maximum speed limit was the 10 mph (16 km/h) limit introduced in the United Kingdom in 1861. The highest posted speed limit in the world is 140 km/h (87 mph), which applies to some roads in Poland and Bulgaria; similarly Texas posts 85 mph (137 km/h) on one 40-mile (64 km) long toll road. However, some roads have no speed limit for certain classes of vehicles.