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【单选题】
图示 T 字形截面,其形心在点 C , y 轴为其对称轴,下列结论中哪些始 正确的 ?( ) (1)x,y轴为主惯性轴,因为它们都通过形心; (2)x,y轴为主惯性轴,因为y轴为对称轴,故Ixy=0; (3)x,y轴均为形心主惯性轴,因为它们既是主惯性轴,又都通过形心; (4)y轴为形心主惯性轴,x轴只是形心轴(心主惯性轴)。A.
(1)
B.
(2)、(3)
C.
(4)
D.
(1)、(3)
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举一反三
【单选题】It can be inferred from the passage that the author most probably believes which of the following to be true concerning those historians who study the history of women?
A.
Their work provides insights important to those examining social phenomena affecting the lives of both sexes.
B.
Their work can only be used cautiously by scholars in other disciplines.
C.
Because they concentrate only on the role of women in the work-place they draw more reliable conclusions than the other historians.
D.
Their work has not had an impact on most historians' current assumptions concerning the revolutionary effect of technology in the work-place.
【简答题】阶级斗争:阶级斗争是 根本冲突的 之间的 和 。它根源于阶级之间 的根本对立,根源于社会 的冲突。一切阶级斗争,归根结底都是围绕着 这个轴心展开的。
【单选题】Congratulations on purchasing from our company the C800 Coffee Maker, which is suitable for home use.
A.
我公司隆重推出C800型家用咖啡壶，欢迎各界人士惠顾。
B.
您从我公司购买的最新款的C800型家用咖啡壶，值得祝贺。
C.
恭喜您购买本公司田00型咖啡壶，此款咖啡适合居家使用。
D.
您购买的咖啡壶是我公司最新产品—C800家用型，特此致谢。
【多选题】阶级斗争
A.
是阶级利益根本冲突的对抗阶级之间的对立和斗争
B.
根源于阶级之间物质利益的根本对立，根源于礼会经济关系的冲突
C.
是社会基本矛盾在阶级社会中直接表现
D.
是阶级社会发展的直接动力
【单选题】It can be inferred from the passage that Davis’ paradigm does NOT apply to which of the following?
A.
The shoreline of Florida mangrove forests first studies by Davis
B.
A shoreline in an area with weak currents
C.
A shoreline in an area with weak idal energy
D.
A shoreline extended by “land-building” species of mangrove
E.
A shoreline in which few sediments can accumulate
【单选题】I’m afraid none of them can ________ the machine that has been imported from abroad. Which of the following is wrong?
A.
work
B.
run
C.
turn
D.
operate
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