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问题 推断题

下图表示由某烃A合成饱和酯G（C6H10O4）的过程

（1）写结构简式：D_____________，G______________。

（2）写化学方程式：

① E→ F：______________________

② D + F→ G：______________________

答案

（1）CH3COOH；CH3COOCH2CH2OOCCH3

（2）①Br-CH2CH2-Br+2NaOHHO-CH2CH2-OH+2NaBr；

②2CH3COOH+ HO-CH2CH2-OHCH3COOCH2CH2OOCCH3+2H2O

单项选择题

( )是通过投标而被选中承揽设备的设计任务、制造任务、储运任务、安装任务和调试任务的设备工程承包单位。

A．业主
B．监理师
C．承包商
D．分包商
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单项选择题

In the following essay, each blank has four choices. Choose the best answer and write down on the answer sheet.
The purpose of the testing phase of software development is not to (21) the absence of errors in the programs being tested, but rather to find as many errors as possible. This statement may seem to contradict one’s intuitive notion of a successful test of a piece of (22) ; however, a successful test is one in which errors have been found, net one in which no errors have been detected.
There are generally two kinds of testing method: human testing and machine testing. In most companies where systems are developed, the first testing that occurs is not machine testing, but rather the detection of errors through (23) , team efforts, referred to as walkthroughs and inspection. With these methods, the author of the program forms a group with others who represent programming expertise or who may be part of the project team.
After code has been subjected to the manual testing described above, it is then machine test- ed. Again, the test cases are designed to detect the (24) number of errors. Incremental or integration testing occurs subsequent to unit testing. This means combing modules with those that have already been unit tested. The incremental approach not only tests the (25) of each module, but also the "rippling effects" of errors, and the interfaces among modules.

A) program B) codeC) testD) software
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