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【单选题】
若数列{a n }的前n项和S n =2n 2 -2n，则数列{a n }是（ ）A.
公差为4的等差数列
B.
公差为2的等差数列
C.
公比为4的等比数列
D.
公比为2的等比数列
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【单选题】If the president wants to put a treaty into effect, he has to get the approval by two thirds of the _____.
A.
Senate
B.
Cabinet
C.
Congress
D.
The Supreme Court
【简答题】体育锻炼能使心肌发达，收缩有力，心脏工作潜力大。如表是安静状态时反映甲、乙两同学心脏工作能力的数值，根据表格探究以下问题。 (1)计算两位同学的每搏输出量并填入表中。 (2)根据两位同学的每搏输出量，判断甲、乙两同学哪位是运动员，并写出判断的理由：_____，__________________。 (3)假如剧烈运动时，甲、乙两同学的最高心率均相同，每分输出量越大，心脏工作潜力越大，试判断甲、乙两...
【单选题】If the president wants to put a treaty into effect, he has to get the approval by two thirds of the （）
A.
Senate
B.
Cabinet
C.
Congress
【单选题】有关动脉血压,正确的是
A.
平均动脉压=(舒张压+收缩压)÷2
B.
正常青年人安静时收缩压在100~120mmHg
C.
舒张压高低主要反映每搏输出量多少
D.
收缩压主要反映外周阻力的大小
E.
动脉血压仅是由于心脏射血形成的
【单选题】The president wants to see their national flag ______ on the surface of Mars by 2019.
A.
to fly
B.
flying
C.
flew
D.
flown
【简答题】The president wants to explore every towards peace in the region. (way)
【单选题】The president wants to promote with China.
A.
friendship
B.
membership
C.
citizenship
D.
musicianship
【单选题】The president wants to improve the nation's highways and mass ____________ systems.
A.
transit
B.
operation
C.
transition
D.
transmission
【判断题】If the president wants to put a treaty into effect, he has to get the approval by two thirds of the senate.
A.
正确
B.
错误
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