2. A model car racer remotely controls a car, which first moves forward $1 \mathrm{~m}$, then rotates counterclockwise by an angle $\alpha\left(0^{\circ}<\alpha<180^{\circ}\right)$, which is called one operation. If after five operations, the car returns to the starting point, then the angle $\alpha$ is ( ).
(A) $72^{\circ}$
(B) $108^{\circ}$ or $144^{\circ}$
(C) $144^{\circ}$
(D) $72^{\circ}$ or $144^{\circ}$
(2005, National Junior High School Mathematics League Wuhan CASIO Cup Selection Competition)
(Tip: Use the theorem of the sum of interior and exterior angles. Answer: D. )