Final answer:
When passing a vehicle, the driver's manual does not suggest that you should assume the other driver does not see you. Instead, it advises using signals and checking mirrors and blind spots to pass safely. Lightly tapping your horn could be applicable in some contexts, but it is not universally recommended.
Step-by-step explanation:
The driver's manual suggests several things to do when you pass a vehicle. Assume the other driver does not see you is not one of the recommended actions. It is important to be aware of the surroundings and other vehicles, but assuming they do not see you is a defensive driving technique and not a recommended practice when actively passing a vehicle. Correct procedures often include using turn signals, checking your mirrors and blind spots, and ensuring you have enough space to pass safely.
When passing another vehicle, it is more common to use your turn signals to indicate your intent to change lanes and to ensure you're passing safely. Lightly tapping your horn might be appropriate in some situations to alert another driver of your presence, but this varies depending on the driving environment and local regulations. Therefore, answer 3) Assume the other driver does not see you is not recommended while passing, as it does not align with the active steps suggested by a driver's manual.