What do 261, 145, and 520 mean in Subject 1?

[FelicityMarie]

In Subject 1, 261, 145, and 520 refer to the visibility on highways, the maximum speed of vehicles, and the minimum distance between vehicles in rainy and foggy weather. In each of the three combinations, the first digit represents visibility, the second digit represents the maximum speed of the vehicle, and the third digit represents the minimum distance between vehicles (where 0 indicates the need to find the nearest exit to leave the highway). Related introduction to Subject 1: 1. Exam content: According to the "Regulations on the Application and Use of Motor Vehicle Driving Licenses," the exam content includes theoretical foundations of driving, road safety laws and regulations, local regulations, and other related knowledge. The exam format is computer-based, with 100 questions, and a passing score of 90 or above. 2. Exam question bank: Since July 2015, the Ministry of Public Security has updated the Subject 1 question bank to 1229 questions, while the question bank for large vehicles remains unchanged. The exam question bank is a unified national version, and there is no such thing as local questions.