用半透膜分离胶体溶液与晶体溶液的方法,叫做()
A.电泳
B.渗析
C.胶溶
D.过滤
E.电解
参考答案:B
—Bad luck! It's too late!
—It doesn't matter. The movie ______ for only a few minutes. You can't miss it. [ ]
A. has begun
B. has been on
C. began
D. was on
下列选项中,属于建筑施工企业安全生产管理机构的主要职责有()。
A.宣传和贯彻国家有关安全生产法律法规和标准
B.编制并适时更新安全生产管理制度并监督实施
C.确实企业安全生产条件所需资金的投入
D.制订企业安全生产检查计划并组织实施
E.组织开展安全教育培训与交流