单项选择题
Which statements about the common heritage of mankind are NOT correct? A、It consists of areas that is not capable of being controlled by any single states. B、Such areas include the high seas, outer space and the Polar regions. C、Such areas do not belong to any single state, and it can be used by all D、The exploitation and exploration of such areas should be for the benefit of mankind.
单项选择题 A B C D
多项选择题 机器人系统为保证被焊工件的一致性，所采用的工装夹具的作用是（）A、保证焊接尺寸B、提高焊接效率C、提高装配效率D、防止焊接变形
不定项选择 光电效应中，入射光强度越大, 遏止电压越高。
