HELP

1. How do you describe the centripetal acceleration and centripetal force on a circulating object?

2. An object is rounding a curve with a centripetal acceleration of 5.0 m/s2. What is the radius of the curve if it moves with a velocity of 12 m/s?

3. What is the speed of a car moving in a circular path with a radius of 25 meters with an acceleration of 1.5 m/s2?

4. If the car in the previous number has a mass of 450 kg, how much centripetal force is acting on it?