【单选题】“必操几杖以从之”是( )礼仪。 选择一项:
【单选题】According to the passage, distance learning is basically characterized by ________.
A.
a minimum or total absence of face-to-face instruction
B.
a considerable flexibility in its academic requirements
C.
the great diversity of students’ academic backgrounds
D.
the casual relationship between students and professors
【单选题】According to the passage , distance learning is basically characterized by_____
A.
A considerable flexibility in its academic requirements
B.
The great diversity of students' academic backgrounds
C.
A minimum or total absence of face-to-face instruction
D.
t the casual relationship between students and professors
【单选题】现有
C.
D四种元素,A是地壳中含量最多的元素;B少量存在于煤中,它燃烧时产生的有刺激性气味的气体是导致酸雨和大气污染的主要原因;C元素的原子核内无中子;D是组成有机物不可缺少的一种元素.试回答下列问题. (1)元素名称:A______,B______,C______,D______. (2)写出下列物质的化学式: ①A的单质______,B的单质______; ②由四种元素中两种元素组成的常温下呈液态的氧化物______; ③由四种元素中两种元素组成,且两种元素的质量比为l:1的化合物______.
【单选题】有人触电后,下面哪种应急措施是正确的( )
A.
就地使用铁器或潮湿的棍棒拨开触电者身上的电线或电器用具
【简答题】According to the passage , distance learning is basically characterized by_____ A) A considerable flexibility in its academic requirements B) The great diversity of students' academic backgrounds C) A...
【单选题】有人触电后,下面哪种应急措施是正确的( )
A.
就地使用铁器或潮湿的棍棒拨开触电者身上的电线或电器用具
C.
站在干燥的木板上或穿上不带钉子的胶底鞋,用两只手拉触电者的干燥衣服