What does 261145520 mean in Subject 1?

[Ramirez]

In Subject 1, 261, 145, and 520 refer to the visibility, maximum speed of vehicles, and minimum distance between vehicles on highways under rainy and foggy weather conditions. The specific details are as follows: 1. 261261 refers to visibility below 200 meters on highways, with a maximum speed of 60 km/h and a minimum distance of 100 meters between vehicles. 2. 145145 refers to visibility below 100 meters on highways, with a maximum speed of 40 km/h and a minimum distance of 50 meters between vehicles. 3. 520520 refers to visibility below 50 meters on highways, with a maximum speed of 20 km/h, and exiting the highway at the nearest exit.