Questions 24-30 ·Look at the questions fo_爱下问搜题

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问题单项选择题

Questions 24-30

·Look at the questions for this part.
·You will hear a passage about "WTO ". You will listen to it twice.
·For Questions 24-30, indicate which of the alternatives A, B, or C is the most appropriate response.
·Mark one letter A, B, or C on the Answer Sheet.

How are trade disputes among WTO member states settled

A．WTO member states refer trade disputes to the WTO dispute panel.

B．WTO member states settle their trade disputes among themselves.

C．WTO member states choose an arbitrator for settlement.

答案

参考答案：A

单项选择题

性激素分泌不足可致（）

A.艾迪生病

B.侏儒症

C.库欣综合征

D.肢端肥大症

E.性幼稚症

实验题

某同学怀疑自来水中可能含有大量Ca²⁺、Mg²⁺ 阳离子和某些阴离子，从而进行了实验探究：

①取少许自来水于试管中，滴加足量的Na₂CO₃溶液，产生白色沉淀；

②过滤后取滤液于试管中，滴加足量的NaOH溶液，又有白色沉淀生成；

③另取少许自来水于试管中，滴加足量HNO₃后再滴加AgNO₃溶液，也产生白色沉淀；

请回答以下问题：

（1）初步确定自来水中_______（是或否）含有大量Ca²⁺、Mg²⁺阳离子；判断依据的离子反应有

_____________________

（2）自来水中所含阴离子可以确定有__________，理由是_________________________。

（3）确定实验①中滴加的Na₂CO₃溶液已过量的检验方法是：___________________________。