【简答题】链传动的 传动比不变, 传动比是变化的。
【简答题】检验淬火钢成品件的硬度一般用______硬度,而布氏硬度适用于测定______的硬度。
【多选题】在创新能力的评价中专门技能的评价是采用一定的创新方法,得到具有一定创新性成果的能力,包括
【单选题】The bad news for the actress.
【单选题】The bad news would become a good one if
A.
people maintain the harmony between the human and the earth.
B.
people in the global village could do something to stop ice from melting.
C.
the researchers in Cambridge University could do more researches.
D.
there is more and more concern and attention on global community.
【多选题】综合来看,幼儿园班级管理的内容主要包括( )几个方面。
【单选题】某电路元件中,按关联方向电流i=10sin (314t-90°)A,两端电压u=220 sin314tV,则此元件的无功功率Q为()。