Final answer:
When coupling a tractor and trailer, it is important to inspect the tires of the trailer and secure the fifth wheel latch.
Step-by-step explanation:
When coupling a tractor and trailer, after backing the tractor up to the trailer, you would typically exit the cab and complete a series of steps to ensure a proper coupling. One of these steps is to inspect the tires of the trailer. This is important to check for any damage or low tire pressure that could affect the safe operation of the trailer. Another step is to secure the fifth wheel latch. The fifth wheel is the device on the back of the tractor that couples with the trailer. It is crucial to properly secure this latch to ensure the trailer is securely attached to the tractor.