皮皮学，免费搜题
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搜题
【单选题】
利用带电粒子在电场作甩下定向移动的特性，对混合物组分进行分离、纯化和测定的技术为
A.
电泳技术
B.
电化学技术
C.
层析技术
D.
超速离心技术
E.
光谱技术
拍照语音搜题，微信中搜索"皮皮学"使用
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举一反三
【单选题】运行D:\ZG\JJ.QPR 查询文件,正确的命令是( )
A.
DO
B.
DO  JJ.QPR
C.
DO  D:\ZG\JJ
D.
DO  D:\ZG\JJ.QPR
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【单选题】大小车轮宜用的材料是()。
A.
ZG25的铸钢
B.
ZG55的铸钢
C.
铸铁
D.
锻钢
查看完整题目与答案
【单选题】灰口铸铁（HT）、球墨铸铁（QT）、铸钢（ZG）三者铸造性能的优劣顺序HT>QT>ZG；塑性的高低顺序为（）。
A.
ZG>QT>HT
B.
HT>QT>ZG
C.
HT>ZG>QT
D.
QT>ZG>HT
查看完整题目与答案
【单选题】要彻底删除D:\ZG\ZGDA.DBF 中男职工的记录,可以使用的命令是( )
A.
USE  D:\ZG\ZGDA DELETE  ALL 性别="男" PACK
B.
USE  D:\ZG\ZGDA DELETE  FOR  性别="男" ZAP
C.
DELETE  FROM  D:\ZG\ZGDA  FOR  性别="男" PACK
D.
DELETE  FROM  D:\ZG\ZGDA  WHERE  性别="男" PACK
查看完整题目与答案
【简答题】Do you have a mobile phone? Do you send text messages to your friends and family? Text messaging or “texting” is becoming very p__1__. But scientists have p__2__ that texting can give us problems with...
查看完整题目与答案
【单选题】What is the result of the 'new form. of discrimination'?
A.
It liberated the non-native English teacher and singled out the unqualified.
B.
It helped the schools to employ those who come from English speaking countries.
C.
It made it easy for the educational organization to select the English teachers.
D.
It proved that the English speakers and the non-English speakers are very similar to each other.
查看完整题目与答案
【简答题】查询D:\ZG\ZGDA.DBF中的姓名、职称、工资字段和D:\ZG\ZGJJ.DBF中的奖金字段的数据,正确的命令是( )A. SELECT  姓名,职称,工资,奖金  FROM  D:\ZG\ZGDA,D:\ZG\ZGJJ   WHERE DA.编号==JJ.编号 B. SELECT  DA.姓名,DA.职称,DA.工资,JJ.奖金  FROM  D:\ZG\ZGDA  DA,D:\ZG\Z...
查看完整题目与答案
【单选题】Which of the following statement is true of native words?
A.
Native words are the core and foundation of the English vocabulary.
B.
Native words are smaller in number compared with the loan words in English.
C.
Native words express the fundamental concepts of meaning and thus are the most frequently used in English vocabulary.
D.
All of the above.
查看完整题目与答案
【单选题】以D:\ZG\ZGDA.DBF为主表,与D:\ZG\JSCJ.DBF表按编号相同建立一对一关系,正确的命令是()
A.
USE  D:\ZG\ZGDA INDEX  ON  编号 TAG BH USE D:\ZG\JSCJ INDEX  ON  编号 TAG BH SET RELATION  TO  编号  INTO  JSCJ
B.
USE  D:\ZG\JSCJ INDEX  ON  编号 TAG BH SELECT  0 USE D:\ZG\ZGDA SET RELATION  TO  BH  INTO  JSCJ
C.
USE  D:\ZG\ZGDA INDEX  ON  编号 TAG BH SELECT  0 USE D:\ZG\JSCJ SET RELATION  TO  编号  INTO  JSCJ
D.
USE  D:\ZG\JSCJ INDEX  ON  编号 TAG BH SELECT  0 USE D:\ZG\ZGDA SET RELATION  TO  编号  INTO  JSCJ
查看完整题目与答案
【简答题】Do you have a mobile phone? Do you often send text messages （短信） to your friends or family? If you keep sending text messages over and over again, there may be something wrong with your fingers. 小题1: ...
查看完整题目与答案
相关题目：
【单选题】运行D:\ZG\JJ.QPR 查询文件,正确的命令是( )
A.
DO
B.
DO  JJ.QPR
C.
DO  D:\ZG\JJ
D.
DO  D:\ZG\JJ.QPR
查看完整题目与答案
【单选题】大小车轮宜用的材料是()。
A.
ZG25的铸钢
B.
ZG55的铸钢
C.
铸铁
D.
锻钢
查看完整题目与答案
【单选题】灰口铸铁（HT）、球墨铸铁（QT）、铸钢（ZG）三者铸造性能的优劣顺序HT>QT>ZG；塑性的高低顺序为（）。
A.
ZG>QT>HT
B.
HT>QT>ZG
C.
HT>ZG>QT
D.
QT>ZG>HT
查看完整题目与答案
【单选题】要彻底删除D:\ZG\ZGDA.DBF 中男职工的记录,可以使用的命令是( )
A.
USE  D:\ZG\ZGDA DELETE  ALL 性别="男" PACK
B.
USE  D:\ZG\ZGDA DELETE  FOR  性别="男" ZAP
C.
DELETE  FROM  D:\ZG\ZGDA  FOR  性别="男" PACK
D.
DELETE  FROM  D:\ZG\ZGDA  WHERE  性别="男" PACK
查看完整题目与答案
【简答题】Do you have a mobile phone? Do you send text messages to your friends and family? Text messaging or “texting” is becoming very p__1__. But scientists have p__2__ that texting can give us problems with...
查看完整题目与答案
【单选题】What is the result of the 'new form. of discrimination'?
A.
It liberated the non-native English teacher and singled out the unqualified.
B.
It helped the schools to employ those who come from English speaking countries.
C.
It made it easy for the educational organization to select the English teachers.
D.
It proved that the English speakers and the non-English speakers are very similar to each other.
查看完整题目与答案
【简答题】查询D:\ZG\ZGDA.DBF中的姓名、职称、工资字段和D:\ZG\ZGJJ.DBF中的奖金字段的数据,正确的命令是( )A. SELECT  姓名,职称,工资,奖金  FROM  D:\ZG\ZGDA,D:\ZG\ZGJJ   WHERE DA.编号==JJ.编号 B. SELECT  DA.姓名,DA.职称,DA.工资,JJ.奖金  FROM  D:\ZG\ZGDA  DA,D:\ZG\Z...
查看完整题目与答案
【单选题】Which of the following statement is true of native words?
A.
Native words are the core and foundation of the English vocabulary.
B.
Native words are smaller in number compared with the loan words in English.
C.
Native words express the fundamental concepts of meaning and thus are the most frequently used in English vocabulary.
D.
All of the above.
查看完整题目与答案
【单选题】以D:\ZG\ZGDA.DBF为主表,与D:\ZG\JSCJ.DBF表按编号相同建立一对一关系,正确的命令是()
A.
USE  D:\ZG\ZGDA INDEX  ON  编号 TAG BH USE D:\ZG\JSCJ INDEX  ON  编号 TAG BH SET RELATION  TO  编号  INTO  JSCJ
B.
USE  D:\ZG\JSCJ INDEX  ON  编号 TAG BH SELECT  0 USE D:\ZG\ZGDA SET RELATION  TO  BH  INTO  JSCJ
C.
USE  D:\ZG\ZGDA INDEX  ON  编号 TAG BH SELECT  0 USE D:\ZG\JSCJ SET RELATION  TO  编号  INTO  JSCJ
D.
USE  D:\ZG\JSCJ INDEX  ON  编号 TAG BH SELECT  0 USE D:\ZG\ZGDA SET RELATION  TO  编号  INTO  JSCJ
查看完整题目与答案
【简答题】Do you have a mobile phone? Do you often send text messages （短信） to your friends or family? If you keep sending text messages over and over again, there may be something wrong with your fingers. 小题1: ...
查看完整题目与答案