Final answer:
When coupling cars, they should be brought together at a speed of about 1-2 mph to ensure a safe and controlled connection.
Step-by-step explanation:
When coupling cars, they should be brought together at a speed of about 1-2 mph. This slow speed is necessary to ensure that the cars can safely connect without causing damage or injury. Coupling at higher speeds can result in a jarring impact and potential collisions.
Coupling at a low speed also allows for better control and alignment of the cars, reducing the risk of misalignment or locking issues. Additionally, the slower speed provides drivers with more time to react and adjust their movement when connecting the cars.