Final answer:
Marsha's mom should advise her to slow down and drive carefully on the avenue compared to the highway.
Step-by-step explanation:
Marsha's mom can advise her to slow down and drive carefully on the avenue compared to the highway. The avenue typically has more traffic, intersections, and pedestrians, so driving at a faster speed can increase the risk of accidents. It's important for Marsha to be cautious and follow the speed limit to ensure her own safety and the safety of others on the road.