1. An automobile with 0.260 m radius tires travels 80,651 km before wearing them out. How many revolutions do the tires make, neglecting any backing up and any change in radius due to wear?

2.An Olympic ice skater spins at 5.25 rev/s. What is the centripetal acceleration of the skater's nose if it is 0.133 m from the axis of rotation? Give your answer in m/s².