【简答题】Q、R、X、Y、Z为周期表中原子序数依次递增的前四周期元素。已知: ①Q为元素周期表中原子半径最小的元素; ②R的基态原子中电子占据三种能量不同的原子轨道,且每种轨道中的电子总数相同; ③Y的基态原子的核外成对电子数是未成对电子数的3倍; ④Z有“生物金属”之称,Z 4+ 离子和氩原子的核外电子排布相同。 请回答下列问题(答题时,Q、R、X、Y、Z用所对应的元素符号表示): (1)Q、R、Y三种元...
【单选题】It can be inferred from the passage that Planck's work led to the development of which of the following?
C.
The internal combustion engine.
【单选题】20100106某种考试共有 75 个试题,每对一题得 2 分,每错一题扣 1 分。某考生最后的分 数是 54 分,则该考生共做对 (6) 题。
【判断题】The development of computers has gone through four generations, each of which was characterized by a major technological development.
【判断题】测量基准选择时,一般选择汽车前纵梁或后纵梁的孔作为基准
【单选题】20100106某种考试共有 75 个试题,每对一题得 2 分,每错一题扣 1 分。某考生最后的分 数是 54 分,则该考生共做对 (6) 题。
【单选题】Development of which of the following is the first sign of respiratory system development?
A.
Tracheoesophageal septum
C.
Tracheoesophageal fistula
D.
Respiratory diverticulum
【判断题】核算和监督两项基本会计职能是相辅相成、辩证统一的关系。会计核算是会计监督的基础和保障,没有核算所提供的各种信息,监督就失去了依据。()