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【单选题】
“天上星星有几颗，7后跟上22个0”这是国际天文学联合会上宣布的消息，用科学计数法表示宇宙空间星星颗数为 [     ]
A.
700×10 20
B.
7×10 23
C.
0.7×10 23
D.
7×10 22
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【单选题】同分异构现象在有机化合物中是非常普遍的。下列各组化合物中互为同分异构体的是 ①CH 3 CH 2 CH 2 CH 3 和(CH 3 ) 2 CHCH 3 ；         ②CH 3 CH 2 OH和CH 3 CH 2 CH 2 OH； ③CH 3 COOCH 2 CH 3 和CH 3 CH 2 CH 2 COOH； ④CH 3 CH=CHCH 3 和CH 3 CH 2 CH=CH 2 ； ⑤ ...
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B.
①③⑤
C.
①③④⑤
D.
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【多选题】下列各组化合物中互为同分异构体的是()。
A.
己烷和2,2-二甲基丁烷
B.
2,2-二甲基丁烷和2-甲基己烷
C.
2-甲基己烷和2,2-二甲基戊烷
D.
戊烷和2,2-二甲基戊烷
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【单选题】下列各组化合物中互为同分异构体的是.( )
A.
丁烷和1-丁烯
B.
1-丁烯和1-丁炔
C.
丁炔和1,3-丁二烯
D.
丁烯和丁炔
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【多选题】Which ones of the following expessions coud you use before paraphrasing others' meaning?
A.
So, what you are saying is that.
B.
If i'm hearing you correctly， you mean.
C.
To put it another way, you mean.
D.
In other words.
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【单选题】Man: Can you come over for dinner tonight? Woman: I'm up to my ears in work, so I'll have to take a rain check. Question: What does the woman mean?
A.
She wants to check the weather before deciding.
B.
She has a problem with her hearing.
C.
She'd enjoy coming to dinner another time.
D.
She wants the man to help her with some work.
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【简答题】端电压恒为 ,与流过它的电流 i 无关的二端元件称为
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【单选题】听力原文：Hello, Ms. Lee. This is Aaron Parks from Axis Corporation. I'm calling to let you know that your presentation yesterday impressed us all. We'd like you to send us a price quote for the Branden pr...
A.
A new product to be launched,
B.
An upcoming presentation.
C.
A date for completion of work.
D.
A bid for a project.
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【判断题】史学界大部分学者对乾隆皇帝的评价不高。()
A.
正确
B.
错误
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【单选题】E-mail From: Megan Campbell To: Marta Apter Marta: I'm sorry I didn't respond to your e-mail earlier. I had a problem with my e-mail system for a few days, and I wasn't able to retrieve new messages. ...
A.
To apologize to Marta for not finishing an assignment
B.
To tell Marta she will accept an assignment
C.
To tell Marta she will be unable to complete an assignment on time
D.
To explain to Marta her problems with an assignment
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相关题目：
【单选题】同分异构现象在有机化合物中是非常普遍的。下列各组化合物中互为同分异构体的是 ①CH 3 CH 2 CH 2 CH 3 和(CH 3 ) 2 CHCH 3 ；         ②CH 3 CH 2 OH和CH 3 CH 2 CH 2 OH； ③CH 3 COOCH 2 CH 3 和CH 3 CH 2 CH 2 COOH； ④CH 3 CH=CHCH 3 和CH 3 CH 2 CH=CH 2 ； ⑤ ...
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B.
①③⑤
C.
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D.
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【多选题】下列各组化合物中互为同分异构体的是()。
A.
己烷和2,2-二甲基丁烷
B.
2,2-二甲基丁烷和2-甲基己烷
C.
2-甲基己烷和2,2-二甲基戊烷
D.
戊烷和2,2-二甲基戊烷
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【单选题】下列各组化合物中互为同分异构体的是.( )
A.
丁烷和1-丁烯
B.
1-丁烯和1-丁炔
C.
丁炔和1,3-丁二烯
D.
丁烯和丁炔
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【简答题】高血压:成人在休息安静状态下,动脉的 ≥ 140mmHg 、 ≥ 90mmHg 为高血压。
查看完整题目与答案
【多选题】Which ones of the following expessions coud you use before paraphrasing others' meaning?
A.
So, what you are saying is that.
B.
If i'm hearing you correctly， you mean.
C.
To put it another way, you mean.
D.
In other words.
查看完整题目与答案
【单选题】Man: Can you come over for dinner tonight? Woman: I'm up to my ears in work, so I'll have to take a rain check. Question: What does the woman mean?
A.
She wants to check the weather before deciding.
B.
She has a problem with her hearing.
C.
She'd enjoy coming to dinner another time.
D.
She wants the man to help her with some work.
查看完整题目与答案
【简答题】端电压恒为 ,与流过它的电流 i 无关的二端元件称为
查看完整题目与答案
【单选题】听力原文：Hello, Ms. Lee. This is Aaron Parks from Axis Corporation. I'm calling to let you know that your presentation yesterday impressed us all. We'd like you to send us a price quote for the Branden pr...
A.
A new product to be launched,
B.
An upcoming presentation.
C.
A date for completion of work.
D.
A bid for a project.
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【判断题】史学界大部分学者对乾隆皇帝的评价不高。()
A.
正确
B.
错误
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【单选题】E-mail From: Megan Campbell To: Marta Apter Marta: I'm sorry I didn't respond to your e-mail earlier. I had a problem with my e-mail system for a few days, and I wasn't able to retrieve new messages. ...
A.
To apologize to Marta for not finishing an assignment
B.
To tell Marta she will accept an assignment
C.
To tell Marta she will be unable to complete an assignment on time
D.
To explain to Marta her problems with an assignment
查看完整题目与答案
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