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问题 选择题

下列变化必须加入还原剂的是（　　）

A．NaHCO3→CO2

B．KClO3→KCl

C．FeO→Fe3O4

D．KMnO4→MnCl2

答案

A．元素化合价没有发生变化，不是氧化还原反应，故A错误；

B．无需加入还原剂，在催化剂条件下可自身发生氧化还原反应生成KCl，故B错误；

C．Fe元素化合价升高，需加入氧化剂才能实现，故C错误；

D．Mn元素化合价降低，需加入还原剂才能实现，故D正确．

故选D．

阅读理解

My name is Peter and I’m 12 years old. I don’t have a brother or a sister. I am in No.2 Middle School. My parents are Gray and Nancy Wilson. My father is a worker and my mother is a music teacher.

My father’s parents are David and Jacy Wilson. They don’t live with us. They live in the nearby city（附近的城市）. David is 63 and Jacy is 61. They come to see us once a month（一个月一次）.

My mother’s parents are Henry and Sara Smith. Henry is 62 and Sara is 58. They are farmers. They have a farm. They grow vegetables and rice（种植蔬菜和水稻）. I like to go to see my grandparents.

小题1:How many children do Gary and Nancy Wilson have?

A．One.

B．Two.

C．Three.

D．Four.小题2: Nancy Wilson is a(n)         .

A．worker

B．music teacher

C．farmer

D．We don’t know小题3:        is Nancy Wilson’s father.

A．David Wilson

B．Jacy Wilson

C．Henry Smith

D．Sara Smith小题4: How old is Jacy Wilson?

A．63.

B．58

C．62.

D．61.小题5:Who has a farm?

A．Mr. and Mrs. Wilson.

B．Peter’s parents.

C．Mr. and Mrs. Smith.

D．Nobody.
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多项选择题

公债是政府凭借其信誉采取( )的信用方式取得财政收入的形式之一。

A．少投多得

B．有借有还

C．还本付息

D．多投少得

E．风险为零
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