For safety reasons, it is required to install light-reflecting plates on the rear wall of a trailer or a semi-trailer. Hence, which of the following sentences is correct?

1. It is obligatory to install one 30cm X 60cm plate plate at the center of the vehicle’s rear wall.
2. Correct answer: It is obligatory to install 2 plates on a vehicle with a width of more than 150cm. The plates’ outside frame should be red and the rest yellow.
3. Three red/yellow plates should be installed on vehicles with a width of more than 200cm.
4. The plates will only be installed according to the requirements of the Licensing Bureau and in accordance with the directions of the chief examiner.

WhyA vehicle wider than 150 cm must have two reflective plates at the rear: yellow with a red outer frame.