Answer:
the normal force that is perpendicular to the surface has a component towards the center of the curve.
Step-by-step explanation:
When curves with superelevation or inclination, the normal force that is perpendicular to the surface has a component towards the center of the curve. This component is what maintains the vehicle and gives it centripetal acceleration.
Consequently, the vehicle does not need the friction force since it does not have a tendency to slide and this is zero.