Which of the following are true about Xiang Yu? A: a prominent military leader and political figure during the late Qin Dynasty. B: In 207 BC, Xiang Yu led the Chu rebel forces to Victory at the Battle of Julu(巨鹿之战) against the Qin armies. C: After the fall of the Qin Dynasty, Xiang Yu proclaimed himself＂ Hegemon- King of Western Chu＂(西楚霸王)and ruled a vast area of land. D: He engaged Liu Bang, in a long struggle for power, known as the Chu- Han Contention(楚汉之争).