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【简答题】
游离香豆素及其苷分子中具有()结构,在()中可水解开环,形成溶于水的()。加酸又环合成难溶于水的内酯结构而沉淀析出。利用此反应特性,可用于香豆素及其内酯类化合物的鉴别和提取分离。
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【单选题】In 1882, what Act(法案) was signed by President Arthur?
A.
Federal Immigration and Nationality Act.
B.
The Chinese Exclusion Act.
C.
Alien Act.
D.
Chinese Immigration Act.
【简答题】工作区子系统设计中,每 _ (1)__ 平方米为 1个工作区,对于增强型设计等级,每个工作区安排 __(2)__ 个信息插座。
【简答题】What made the Forest Service comply with the Enered Species Act?
【简答题】What do the occurring gasses above us act as?
【简答题】A．A bank clerk. B．A clerk in a post office. C．A school teacher. D．A shop assistant.
【单选题】What does the first Act accomplish in a typical narrative movie?
A.
It is the act of telling the story
B.
To repeat the motif from the beginning
C.
To get prepared for the final climax, grabbing the attention and sparking the curiosity of the viewers
D.
To introduce the setting and characters and to establish what and who they are
【多选题】What was the Homestead Act of 1862?
A.
It was a law signed by President Abraham Lincoln on May 20, 1862.
B.
It was a law signed by President Abraham Lincoln on May 20, 1887.
C.
In 1862, the Homestead Act was passed and signed into law. This Act provided that any person who claimed a plot of public land , or a homestead, on the Great Plains and farmed it for 5 years would be given 160 acres.
D.
In 1862, the Homestead Act was passed and signed into law. This Act provided that any person who claimed a plot of public land , or a homestead, on the Great Plains and farmed it for 20 years would be given 180 acres.
【单选题】What is the role of the Civil Rights Act of 19? The aim of the Act is to______.
A.
forbid the diversity of the college students
B.
unify the racial composition of students and faculty
C.
influence student admission guidelines, financial aid distribution, and faculty hiring procedures.
D.
make students at colleges and universities in the United States more diverse and have no racial discrimination
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