A runner is training for an upcoming marathon by running around a 100-m-diameter circular track at constant speed. Let a coordinate system have its origin at the center of the circle with the x-axis pointing east and the y-axis north. The runner starts at (x, y) = (50 m, 0 m) and runs 2.5 times around the track in a clockwise direction. What is his displacement vector? Give your answer as a magnitude and direction?