正常成人输尿管内径的超声测值为（）。
A.2～4mm
B.4～6mm
C.6～8mm
D.8～10mm
E.10～12mm
参考答案：A
Where ___________ your father usually ___________ lunch?[ ]
A. do; have
B. are; having
C. does; have
对汽轮机的油系统有哪些基本要求？
