【单选题】In a modern three-phase A.Csynchronous brushless generator, the excitation winding is on the rotorThat means _____. A.The generator needs not excitation
B.
The winding on the rotor is for inputting excitation current
C.
There are three phase windings on the rotor
D.
The generator has brushes
【单选题】The science of wildlife management is actually quite new. It is the third major phase of the original conservation movement. The first phase involved the preservation of wildlife through laws and hunt...
A.
the history of the wildlife conservation movement
B.
the preservation of wildlife through laws
C.
wildlife management as a new approach
D.
protection and improvement of the habitat of animals
【单选题】混凝土结构工程按冬期施工要求组织施工的前提是:根据当地多年气温资料,室外日平均气温连续稳定低于5C°的天数为( )
【判断题】在胃癌和食管癌患者,有时癌细胞可经胸导管、再由颈干逆流转移到左锁骨上淋巴结,引起左锁骨上淋巴结的肿大。()
【单选题】乒乓球球台的上层表面叫做比赛台面,是与水平面平行的长方形,长 68.5px,宽3812.5px,离地面高( )。
【单选题】下列关于舞会的说法中错误的是()。
D.
舞会一般在周末、节假日或者开幕式、闭幕式的晚会举行
【单选题】胃癌和食管癌患者,癌细胞可经胸导管转移,引起哪个淋巴结肿大
【单选题】设根结点的层数为0,若高度为h的二叉树上只有度为0和度为2的结点,则此二叉树上所包含的结点数至少为()。