A particle moves on a circle of radius 5 cm, centered at the origin, in the xy- plane (x and y measured in centimeters) . It starts at the point (0,5) and moves counterclockwise, going once around the circle in 8 seconds. a) Write a parameterization for the particle's motion. b) What is the particle's speed? Give units. c) What is the particle's acceleration vector? Give units