The teacher and writer _____ the lecture. It'll be finished in half an hour. [ ]

A. have gone to

B. have been to

C. has gone to

D. has been to

关于渗透泵型控释制剂，正确的叙述为（）

A.渗透泵型片剂与包衣片剂很相似，只是在包衣片剂的一端用激光开一细孔，药物由细孔流出

B.渗透泵型片剂的释药速度受pH影响

C.半渗透膜的厚度、渗透性、片芯的处方、释药小孔的直径是制备渗透泵的关键

D.渗透泵型片剂以一级释药，为控释制剂

E.渗透泵型片剂工艺简单