Final answer:
The question is about when it is not safe to pass another vehicle based on specific driving and traffic laws.
Step-by-step explanation:
The subject of this question is about driving and traffic laws, specifically about when it is not safe to pass another vehicle. According to the information provided, you must not pass when there is a double solid line or a solid dividing line on the lane you're driving in, when approaching a curve or the top of a hill where visibility is limited, when approaching within 100 feet of a street crossing, a railroad crossing, or a bridge, tunnel, or underpass where your view is blocked.