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问题 选择题

关于盐酸、硫酸、硝酸叙述错误的是

A．三者都是强酸，其稀溶液中只有稀硝酸与铜在常温反应

B．浓盐酸制氯气，浓硫酸使纸张变黑，浓硝酸常温与铜反应，体现了三者的强氧化性

C．将强氧化性的浓硫酸与浓硝酸按比例混合可以得到氧化性更强的王水

D．铝、铁在冷的浓硫酸或浓硝酸的钝化属于化学反应

答案

BC

改错题

改错。下列各旬均有一处错误，请选择其序号并在后面的横线上改正。

1. The doctor will be  free after ten minutes.                                          ________

                       A   B          C

2. The doctor told the patient to take the medicine each four hours.       ________

                       A                       B                           C

3. Miss Yang is very funny and she always makes me to laugh.              ________

                                  A                                 B              C

4. Mike gets to home at about six in the afternoon.                                ________

               A        B                       C  

5. Last Sunday our team win the football match.                                    ________

           A                          B                      C

6. Holly is more outgoing than  I  do.                                                    ________

                           A           B       C

7. You need buying a new computer because yours is too old.               ________

                       A                                              B           C

8. She got three apples and then cut up them.                                        ________

            A                              B          C

9. He is  a unusual boy.                                                                         ________

     A      B    C

10. I am sorry you didn't have fun in your day off.                                 ________

                 A             B                C
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单项选择题

某公司生产甲产品，一季度至四季度的预计销售量分别为1000件、800件、900件和850件，生产每件甲产品需要2千克A材料。公司的政策是每一季度末的产成品存货数量等于下一季度销售量的10%，每一季度末的材料等于下一季度生产需要量的20%。该公司二季度的预计材料采购量为( )千克。

A．1600

B．1620

C．1654

D．1668
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