Kim has her coffee cup on her car's dash when she takes a corner with radius 4 m and 20 km/h. What is the minimum coefficient of static friction which would allow the coffee cup to stay there without slipping?

I know how to complete the question. However, I was wondering what forces are the ones causing the centripetal force? My original thought was static friction, but I am unsure if static friction can act in two directions at once. Thanks!