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【单选题】
已知 为x(n) 的离散时间叶变换 (DTFT) , 若 将x(n) 分成共轭对称部分 x e ( n ) 和共轭反对称部分 x o ( n ) ,则 x e ( n ) 的 DTFT 对应 的________;若将 分成实部 和虚部 ,则 的 DTFT 对应 的___________ 。 ()A.
虚部；共轭反对称分量
B.
虚部；共轭对称分量
C.
实部；共轭反对称分量
D.
实部；共轭对称分量
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【单选题】我国谚语中的“螳螂捕蝉，黄雀在后”体现了食物链的原理。若鹰迁入了蝉、螳螂和黄雀所在的树林中，捕食黄雀并栖息于林中。下列叙述正确的是
A.
鹰的迁入增加了该树林中蝉及其天敌的数量
B.
该生态系统中细菌产生的能量可流向生产者
C.
鹰的迁入增加了该生态系统能量消耗的环节
D.
鹰的迁入改变了该生态系统能量流动的方向
【单选题】'When one of the doctors criticizes(批评) me, I get defensive. I feel like a child again, being scolded, and I want to explain that I'm not wrong.' says Viola, a nurse. This is a common reaction(反应) to ...
A.
argued bitterly with his employer
B.
was angry and gave up his job
C.
was sorry for what he did
D.
was sad and self-pitying
【单选题】我国谚语中的“螳螂捕蝉,黄雀在后”体现了食物链的原理。若鹰迁入了蝉、螳螂和黄雀所在的树林中,捕食黄雀并栖息于林中。下列叙述正确的是
A.
鹰的迁入增加了该树林中蝉及其天敌的数量
B.
该生态系统中细菌产生的能量可流向生产者
C.
鹰的迁入增加了该生态系统能量消耗的环节
D.
鹰的迁入增加了该生态系统能量流动的方向
【单选题】'When one of the doctors criticizes(批评) me, I get defensive. I feel like a child again, being scolded, and I want to explain that I' m not wrong. 'says Viola, a nurse. This s a common reaction(反应) to ...
A.
argued bitterly with his employer
B.
was angry and gave up his job
C.
was sorry for what he did
D.
was sad and self-pitying
【单选题】—I’m sorry, but I didn’t mean out your secret. —But you know, letting out one’s secret means one’s feelings.
A.
to let; to hurt
B.
letting; hurting
C.
to let; hurting
D.
letting; to hurt
【单选题】听力原文：M: Wow. I slept like a log. For one, I really feel rested and ready to go. W: Hold it a second. How about treating ourselves to breakfast in bed for a change. Q: What can we learn from this dialo...
A.
They had a sound sleep last night.
B.
They had a telephone call, but the line was engaged.
C.
They stayed in bed.
D.
After breakfast, she would go to see a doctor for treatment.
【简答题】What is NOT true of the effectiveness of 'sunscreen', according to the last paragraph?
【单选题】According to the fifth parag,aph，what is the suggested method to control underground fires?
A.
Using remote sensing technique．
B.
Controlling the release of carbon dioxide．
C.
Making the soil heat resistant．
D.
Cutting off the oxygen supply．
【单选题】'When one of the doctors criticizes me, I get defensive. I feel like a child again, being scolded, and I want to explain that I'm not wrong,' says Viola, a nurse. This is a common reaction to criticis...
A.
argued bitterly with his employer
B.
was angry and gave up his job
C.
was sorry for himself
D.
was sad but confident
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