A bug is crawling along the spoke of a wheel that lies along a radius of the wheel. The bug is crawling at unit per second and the wheel is rotating at radian per second (counterclockwise when looked at from the positive axis). Suppose the wheel lies in the -plane with center at the origin, and at time the spoke lies along the positive -axis and the bug is at the origin. Find a vector function for the position of the bug at time .