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问题 单项选择题

用铬酸钾作为指示剂，用硝酸银滴定液滴定氯化物、溴化物时，应当在

A．在中性溶液中进行
B．在强酸性溶液中进行
C．在强碱性溶液中进行
D．在弱酸性溶液中进行
E．在弱碱性溶液中进行

答案

参考答案：A

完形填空

阅读短文,在其后空白处写出各单词的正确形式。单词的第一个字母已经给出。

Fred didn’t like to use his head. He never put his heart into his studies when he was at school. So he f小题1: behind his classmates and couldn't pass the exams. Before long he l 小题2: school and stayed at home. With his father’s help, he found a job in a factory. At first he worked in an office, but he was u  小题3: to do his job well. So he was sent to a workshop. He had to do some heavy work there. He was always tired when he got home and went to bed as soon as he finished s 小题4:  .

One day, he went to have his long hair cut. He found the work clean and l小题5:. He decided to be a barber, too. So he left the factory. He t小题6: a barber as his teacher. Three month passed, but he didn’t learn anything and the barber lost his p   小题7:  . The young man had to go home. His father helped him to open a barber’s in their town, but nobody would have their hair cut in his shop. His father wanted others to b      小题8:  .Fred and decided to be the first customer.

However, the young man was so c 小题9:    that he hurt his father’s ear. His father shook his head s 小题10:  and said, “Have you ever done something nicely?” “Oh, Dad, I’m dreaming of it.”
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单项选择题 A1/A2型题

伤寒沙门菌引起伤寒症状，除伤寒沙门菌外的其他致菌性沙门菌能够引起食物中毒。沙门菌属中引起食物中毒最常见的菌种为（）

A.鼠伤寒沙门菌

B.肠炎沙门菌

C.鸭沙门菌

D.猪沙门菌

E.伤寒沙门菌
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