勘察设计单位资质实行分级管理审批,甲级资质由( )审批。
A.国务院建设行政主管部门
B.各省、自治区、直辖市建设行政主管部门
C.国家技术监督局
D.工商管理部门
参考答案:C
You have never seen such a wonderful film before, __________ ? [ ]
A. haven't you
B. have you
C. do you
D. don't you
波纹塔板的结构及精馏过程有何特点?