题目

 I have spenton this job. I think I can finish it this afternoon.           A. sometime; sometime                  B. sometimes; some time           C. some time; sometime               D. some times; some time 答案：C已知⊙O的半径为6cm，直径CD⊥弦AB，点F在⊙O上，∠CFA=60°.则AB = ____   ___cm.