Acar with a mass of 2,000 kilograms is moving around a circular curve at a uniform velocity of 25 meters per second. the curve has a radius of 80 meters. what is the centripetal force on the car?
a. 20,250 n
b. 15,625 n
c. 625 n
d. 703 n

Mary starts from her house, walks 80 meters south, and stops to chat with her aunt on the sidewalk. after chatting for a few minutes, she walks 125 meters to the west to meet a friend and then walks 45 meters north with her friend to a cafe for lunch. overall, she takes 10 minutes to do all this. what is mary’s average speed?