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问题 选择题

某微粒Rm-的核电荷数为n，你认为不可能据此推测出的是（　　）

A．该微粒的质子数

B．该微粒所属元素种类

C．该微粒的电子数

D．该微粒的相对粒子质量

答案

A、由题意可知该微粒Rm-的核电荷数为n，核内质子数=核电荷数，故该微粒的质子数为n；

B、质子数决定元素种类，由质子数可知该微粒所属元素种类；

C、该微粒是由原子得到m个电子形成的，故该微粒的电子数为n+m；

D、相对原子质量等于质子数+中子数，因不能确定中子数，故不能确定该微粒的相对粒子质量．

故选D

单项选择题

Audition简易混响视窗中参数早反射时间指（）。

A.直达声到达人耳及早期反射声到达人耳之间的时间间隔值

B.最早的反射声到达人耳的时间

C.早期反射声与晚期反射声到达人耳之间的时间间隔值

D.以上选项都不正确
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改错题

改错。

( ) 1. Do you know the girl of black hair  and big eyes? 　　　　　　                                          

                           A               B           C    D

(     ) 2. It's a pity, but I can do anything about it.                                                                            

                             A      B            C        D

(     ) 3. We were late for school again, because our teacher was very angry.                                      

                                 A               B         C                        D

( ) 4. Take our advices. Leave it to us and go back to have a rest.                                                  

                              A          B      C                 D

( ) 5. He never  tell  a lie  to us. 　                                                                                               

                    A      B    C    D

(     ) 6. The boy need some money. He wants to buy a computer.                                                      

                           A       B                      C        D

(     ) 7. "It's  raining."  "And it is."                                                                                                   

               A       B           C     D

( ) 8. If you want to get along well with others, you have to control your sick temper.                      

                                       A                B      C                                           D

(     ) 9. "It looks like raining." "I'm not afraid so. Look at the sun."                                                     

                   A             B                       C              D

( ) 10. "I'm sorry I may be a little late." "It doesn't the matter."                                                        

                        A        B          C                            D

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