DOT raised the speed limit on a particular stretch of road from 55 to 70 MPH. There is a curve on a portion of the road that was designed assuming various poor road conditions using a coefficient of static friction being between the tires and the road surface =0.15. The curve has a radius of 1/4 mile and a bank angle of 2 degrees originally. Is the road safe at the old and new posted speeds? If not, what should the new bank angle be for the road to be safe.