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【单选题】
淬火钢经过低温回火的马氏体叫 ,它保持了淬火马氏体的高强度、高硬度,脆性和残余内应力有所降低,弹性极限有所提高。A.
M
B.
M 回
C.
T 回
D.
S 回
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【简答题】OECD
【简答题】已知两个椭圆的方程分别是 C 1 ：x 2 +9y 2 -45=0， C 2 ：x 2 +9y 2 -6x-27=0、 （1）求这两个椭圆的中心、焦点的坐标； （2）求经过这两个椭圆的交点且与直线x-2y+11=0相切的圆的方程．
【单选题】根据以下材料，回答题 About Turkey Some of the concerns surrounding Turkey's application to join the European Union， to be voted on by the EU's Council of Ministers on December 17th， are economic—— in particular...
A.
Its GDP per head is far lagging behind that of the EU members.
B.
Its inflation rate is still rising.
C.
Its economy grows faster than any EU member.
D.
Its economic resilience is very strong.
【简答题】（1）求与椭圆4x 2 +9y 2 =36 有相同的焦点，且过点（0，3）的椭圆方程． （2）已知椭圆的对称轴为坐标轴，离心率e= 2 3 ，长轴长为12，求椭圆的方程．
【判断题】Turkey joined the EU in 2008 after implementing the necessary political and economic policy changes.
A.
正确
B.
错误
【单选题】A study published in 2011 by the OECD noted that:
A.
the real household income of the unskilled workers in the U.S. increased more in comparison to that of the skilled workers.
B.
in almost all countries real income levels declined over the 20-year period studied.
C.
falling unemployment rates brought gains to low-wage workers and fairly broad-based wage growth.
D.
the gap between the poorest and richest segments of society in some OECD countries had widened.
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