If circumference C = 2 pi r where r is the radius, how long would it take a car to travel once around a circular track with a 80 meter radius if it is traveling 50 m/s ?

Calculate the first and second velocities of the car with four washers attached to the pulley, using the formulas v1 = 0.25 m / t1 , and v2 = 0.25 m / (t2 – t1) where t1 and t2 are the average times the car took to reach the 0.25 and the 0.50 meter marks. record these velocities, to two decimal places, in table e.