我国的少数民族主要分布在（ ） A．东北部、东南部、中部 B．东部、中部、西北部

In his effort to prevent his company from _____, he worked to his limit, thus _____.  [ ]

A. breaking down; breaking down his health    

B. closing down; broke down his health 

C. closing down; his health broke down        

D. breaking down; his health breaking down

招标投标活动的公开原则，要求()要公开。

A．招标活动的信息

B．投标人的情况

C．开标的程序、评标的标准和程序

D．中标的结果

E．评标委员会成员

创业价值包含哪两个方面？

甲醇洗单元开车使用氮气升压时，应防止中、低压系统超压。

大陆漂移说的基本内容。