【单选题】The duty officer and engineer should obey regulation for the speed of the M.Ethat established by ____.
C.
chief engineer and captain consult together
D.
chief engineer and superintend consult together
【单选题】Passage Two Questions 26 to 30 are based on the following passage. Scientists have established that influenza viruses taken from man can cause the disease in animals. In addition,man can catch the dis...
A.
cause ill health in wild birds
B.
do not always cause symptoms in birds
C.
are rarely present in wild birds
D.
change when transferred from animals to man
【判断题】硅二极管的正向管压降约为0.5~0.7V,锗二极管约为0.1~0.3V。
【单选题】In Para. 4, the 'hierarchies' most closely represent ______.
A.
a crucial method of establishing territorial claims
B.
a practical but undesirable consequence of urban life
C.
a misguided division of nature's sacred space
D.
an effort to protect pristine land from development
【单选题】电路如图所示,D 1 、D 2 均为硅管(正向压降0.7V),D为锗管(正向压降0.3V),U=6V,如果二极管的反向电流为V,则流过D 1 、D 2 的电流分别为:()
【单选题】As early as in 1647 Ohio made a decision that flee, tax-supported schools must be established in every town to have 50 households or more.