I need help with this 3 excercise of Dinamic Please

1.When designing a road curve, cars are required to go to a constant speed of 25m/s and acceleration should not exceed 3m/s2. Determine the minimum radius of curvature of the curve

2. The car has a speed of 80 ft/s at point A. The total acceleration has a magnitude of a = 10 ft/s2 and acts in the direction shown. Determine the radius of curvature. at point A and the tangential component of the acceleration.

\fp = 50 m