A proper look-out shall be maintained().
A. only at night
B. only during restricted visibility
C. at night and during restricted visibility
D. at all time
在社会变迁的基本类型中,为了根本变革社会制度,改善生产关系,从而产生的急剧的、对整个社会进行根本改造的社会变迁形式,被称为()
A. 社会改革
B. 自发变迁
C. 社会革命
D. 整体变迁
() means the level for which minimum appropriate protective security measures shall be maintained at all times, threats and exchanging such information with appropriate Contracting Governments.
A. Security level 1
B. Security level 2
C. Security level 3
D. Lowest safety level
不属于乳酸脱氢酶特性的是()。
A. 由4个亚基组成,具有四级结构
B. 5种乳酸脱氢酶同工酶的不同,是M亚基
C. 都催化乳酸脱氢氧化生成丙酸的可逆反应
D. 都含有辅酶NAD+