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问题 单项选择题 A1型题

用两相溶剂分配法分离混合物中各组分的原理是（）

A.各组分的结构类型不同

B.各组分的分配系数不同

C.各组分的化学性质不同

D.两相溶剂的极性相差大

E.两相溶剂的比重相差大

答案

参考答案：B

填空题
读一读,选择合适的单词。

swimming, hiking, but  skate, windy, best, 
because, fall, kites

        Hello, I am Mike. I like doing sports. In spring I go ________  with my parents. Summer is the____
for me, __________  I can swim in the sea. __________is my favourite sports. In ________ , I fly
____________ in the park. It's ______ . I can climb mountains there. I also like to___________ in
winter. Skating is an exciting sport. Winter is cold, _____________ I like it.

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判断题

海关对保税货物监管的基本特征和要求是：批准保税、纳税暂缓、监管延伸。
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