进行天然气置换,氮气置换空气时,测的氧气浓度低于()时合格。
A、1%
B、2%
C、5%
参考答案:A
Mr. Bean constantly get into awkward and absurd situations, which greatly amuses audiences _____ their nationalities and culture.
A.in favor of
B.in terms of
C.according to
D.regardless of
科学技术本身并不具有善恶的道德属性,问题在于它的应用可能有潜在的破坏作用。