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【单选题】
关于二力构件以下说法错误的是( )A.
二力构件与其形状无关
B.
二力构件是指在两力作用下保持平衡的构件
C.
如果一个杆件在一对等大反向共线的力作用下保持平衡，则该杆件可视为二力构件
D.
二力构件只能是直杆，弯曲杆件不能作为二力构件
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举一反三
【单选题】某校中学生参加电视台“异想天开”节目栏的活动,他们指出了下列四个设想方案,哪些从理论上讲是可行的( )
A.
制作一个装置只从海水中吸收内能全部用来做功
B.
汽车尾气中各类有害气体排入大气后严重污染了空气，想办法使它们自发地分离，既清洁了空气，又变废为宝
C.
将房屋顶盖太阳能板，可直接用太阳能解决照明和热水问题
【单选题】下面关于妊娠期高血压描述不正确的是（）
A.
是妊娠期特有的疾病
B.
是造成孕产妇死亡的主要原因之一
C.
我国发病率为9.4%
D.
是围产儿死亡的主要原因
E.
我国发病率为19.4%
【单选题】Paleontologists hypothesize that modern birds evolved from the family of dinosaurs that included Tyrannosaurus rex. This hypothesis would be strongly supported if evidence that dinosaurs from this fam...
A.
Fossilized dinosaurs have shown many birdlike characteristics, such as bone structure and winglike arms.
B.
If birds are in fact the descendants of dinosaurs, then it can be argued that the dinosaurs never really died out.
C.
Flying dinosaurs such as the Pteranodon, which is not thought to have been related to modern birds, do not appear to have had feathers.
D.
Soft tissues such as skin and feathers do not fossilize like bones, and therefore are far less likely to have left permanent evidence in the fossil record.
E.
The thousands of dinosaur fossils excavated by paleontologists represent only a tiny fraction of the billions of dinosaurs that once lived.
【判断题】The traditional family was a nuclear family and the modern family is,too.
A.
正确
B.
错误
【单选题】The design of the modern architecture concentrates on usefulness _____ decoration.
A.
rather than
B.
more than
C.
other than
D.
instead
【单选题】In modern linguistics, speech is regarded as mor ebasic than writing, because_______.
A.
in linguistic evolution, speech is prior to writing
B.
Speech plays a greater role than writing in terms of the amount of information conveyed
C.
Speech is always the way in which every native speaker acquires his mother tongue
D.
All of above
相关题目：
【单选题】下面关于妊娠期高血压描述不正确的是（）
A.
是妊娠期特有的疾病
B.
是造成孕产妇死亡的主要原因之一
C.
我国发病率为9.4%
D.
是围产儿死亡的主要原因
E.
我国发病率为19.4%
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