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【判断题】
用混凝土泵泵送混凝土时出现离析现象时,应立即用压力其他方法冲洗残留的混凝土,泵送间歇时间不宜超过 15分钟 ( )
A.
正确
B.
错误
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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 ...
A.
①②④
B.
①③⑤
C.
①③④⑤
D.
①③④
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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
E.
2,2-二甲基戊烷和2,2,3-三甲基丁烷
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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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【单选题】听力原文：W: Can you speak up a little? I'm having difficulty hearing you. M: All right. Is that better? Q: What can we conclude from the talk? (4)
A.
The woman doesn't like the man.
B.
The man tries to speak more loudly.
C.
The man doesn't want to speak up.
D.
The woman has no problem hearing the man.
查看完整题目与答案
【单选题】某批发企业销售甲商品,第三季度各月预计的销售量分别为1000件、1200件和1100件,企业计划每月月末商品存量为下月预计销售量的20%,下列各项预计中不正确的是( )
A.
8月份期初存货为240件
B.
8月份采购量为1180件
C.
8月份末存货为220件
D.
第三季度采购量为3300件
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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】完形填空。 'I can't believe what I'm hearing!' I thought to myself. Jeff was the last candidate (候选人) for president of Student Council. My best friend Tony came to me and said. 'I'm sorry, Mike. I really t...
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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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【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
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 ...
A.
①②④
B.
①③⑤
C.
①③④⑤
D.
①③④
查看完整题目与答案
【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
E.
2,2-二甲基戊烷和2,2,3-三甲基丁烷
查看完整题目与答案
【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
查看完整题目与答案
【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
查看完整题目与答案
【单选题】听力原文：W: Can you speak up a little? I'm having difficulty hearing you. M: All right. Is that better? Q: What can we conclude from the talk? (4)
A.
The woman doesn't like the man.
B.
The man tries to speak more loudly.
C.
The man doesn't want to speak up.
D.
The woman has no problem hearing the man.
查看完整题目与答案
【单选题】某批发企业销售甲商品,第三季度各月预计的销售量分别为1000件、1200件和1100件,企业计划每月月末商品存量为下月预计销售量的20%,下列各项预计中不正确的是( )
A.
8月份期初存货为240件
B.
8月份采购量为1180件
C.
8月份末存货为220件
D.
第三季度采购量为3300件
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】完形填空。 'I can't believe what I'm hearing!' I thought to myself. Jeff was the last candidate (候选人) for president of Student Council. My best friend Tony came to me and said. 'I'm sorry, Mike. I really t...
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.
查看完整题目与答案
【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