A model airplane is flying on a guide wire (see attached drawing). Both tangential acceleration aT and centripetal acceleration ac are not equal to zero. Determine which of the following statements are true; the tangential speed (Vr) is a constant, the centripetal force required for the plane to stay on circular motion is (Fc = mac), where (m) is the mass of the plane, the angular speed (CD) is a constant, the angular acceleration (a) is equal to zero, or, both the direction and the magnitude of the tangential velocity are changing with time.