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【单选题】
使用一种与水不互溶的有机溶剂萃取某有机物，设分配系数K=0.3，即该有机物在水中的溶解度与有机溶剂中的溶解度之比为3：10。现以12毫升有机溶剂萃取含1克有机物的水溶液10毫升，分别采用取法和分两次萃取法。两种方法的萃取率E（E等于溶质在有机相中的质量占两相中溶质总质量的百分比）分别为A.
80% 89%
B.
80% 96%
C.
20% 11%
D.
20% 4%
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【简答题】1 g cause (someone) to change their beliefs or ideas (para 3) 2 doing what one is ordered to do (para 3) 3 a person who pays for professional services from a lawyer or a bank (para 6) 4 completely (pa...
【简答题】Word Search (Section A) Find a Word in Text I of Section A which means: 1. cause (someone) to change their beliefs or ideas (Text I, Para. 3) 2. doing what one is ordered to do ( Text I, Para. 3 ) 3. ...
【单选题】下面有关测试原则的说法中正确的是______。 A) 测试用例应由测试的输入数据和预期的输出结果两部分组成 B) 测试用例只需选取合理的输入数据 C) 程序最好由编写该程序的程序员自己来测试 D) 使用测试用例进行测试是为了检查程序是否做了它该做的事
A.
B.
C.
D.
【单选题】Choose the best topic sentence for the following paragraphs. Note that there is one extra sentence which you do not need to useScratching the nose or breaking eye contact, for example, are both sure s...
A.
Your face should be open and friendly, inviting conversation from the interviewer.
B.
Small details, such as posture, or the way you hold your head, have a greater impact than you can imagine
C.
One interviewer we surveyed said she pays a lot of attention to a candidate’s body language
D.
Candidates should keep their answers to the point, without being monosyllabic
【单选题】A person who pays for the right to live in a residence owned by someone else
A.
transition
B.
herald
C.
array
D.
tenant
【简答题】cause (someone) to change their beliefs or ideas:____________ 2 . doing what one is ordered to do:_____________________ 3. a person who pays for professional services from a lawyer or a bank_________...
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