赞题库-背景图

单项选择题

卡塞格伦天线的缺点为【】

A．副瓣电平升高
B．馈线长度可减小
C．纵向尺寸小
D．馈源失配高

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热门试题

多项选择题下列有关项目决策树的说法，正确的有()。

A.决策树是一个从左至右一次展开的树状图
B.决策树只能进行单级决策
C.决策树的分级越多，决策树图就会越复杂
D.决策树能够使项目管理者有步骤地进行决策

单项选择题Which of the following is NOT true in terms of the major information in each section of a research article ?

A．Researchers usually explains why they conducted the research in the Introduction section.
B．Researchers usually explains thoroughly the findings they obtained in the Results section.
C．Researchers usually explains how they conducted the research in the Methods section.
D．Researchers usually reported their conclusion about the research in the Discussion section.