头颅侧位是临床经常拍摄的摄影位置。头颅侧位摄影中心线经（） A.外耳孔前、上各0.5

—Daniel can't _____ his English book. Can you help him?     

—Ask him to _____ it in his bag. [ ]

A. see, look after    

B. look after, see

C. look for, find  

D. find, look for

秦腔的领奏乐器是：（）

A.京胡 

B.高胡 

C.板胡 

D.坠胡

500kV交流等电位作业人员对相邻导线的距离应不小于3.4m。