在汉朝关中水利图上，连接泾、渭二水的是（）。 A.郑国渠 B.白渠 C.六辅渠

关于库仑定律，下列说法中正确的是（　　）

A．库仑定律适用于点电荷，点电荷其实就是很小的球体

B．根据F=K

Q1Q2

r2

，当两点电荷间的距离趋于零时，库仑力将趋向于无穷大

C．若点电荷Q₁的电荷量大于Q₂的电荷量，则Q₁对Q₂的库仑力大于Q₂对Q₁的库仑力

D．库仑定律和万有引力定律的表达式相似，都是平方反比定律

Dr. Kate: Radio _小题1:  (change) a lot since we were young. It used _ 小题2: be the major source of' fun for the family.

Bob:      Nowadays when you turn on the radio, you either hear music, a talk show小题3: news.

Dr. Kate: 小题4:  (Fortunate), you can choose the kind of music you want to hear.

Bob:      Yes, and there is a lot of points of view when you listen to talk shows. I usually enjoy  小题5:  (listen) to them. I particularly like it w-hen a caller disagrees with the talk show host. I like to hear how he will defend his ideas.

Dr. Kate: Some talk show hosts are very rude to those  小题6: have opposing ideas. I really find that terrible.

Bob:     It seems that people only listen to the radi0  小题7:  they are driving in their car ，

Dr. Kate: That is true for me. but I know that my husband listens to it while he is working  小题8: home.

Bob:   Now that f think about it, I realize that a lot of stores have the radi0  小题9:  (play).

Dr. Kate: It's still a usefully and pleasant form of  小题10: (communicate).

有A、B、C、D四种主族元素，A、B元素的阳离子和C、D元素的阴离子都具有相同的电子层结构，且A的阳离子氧化性比B的阳离子氧化性弱，C的阴离子所带负电荷比D的阴离子所带负电荷多，则A、B、C、D的原子序数大小关系是（    ）D

A．B>A>C>D       B．C>B>A>D         C．A>B>C>D         D．B>A>D>C

（12分）非金属单质A经如图所示的过程转化为含氧酸D，已知D为强酸，请回答下列问题：

（1）若A在常温下为固体，B是能使品红溶液褪色的有刺激性气味的无色气体。

①D的化学式是________；

②在工业生产中B气体的大量排放被雨水吸收后形成了________而污染了环境。

（2）若A在常温下为气体，C是红棕色的气体。

①A、C的化学式分别是：A________；C________.

②D的浓溶液在常温下可与铜反应并生成C气体，请写出该反应的化学方程式___________________________。该反应________（填“属于”或“不属于”）氧化还原反应。

一本书初版时共印了10000册，每卖出一册，该书作者可得0.8元，后再版，这时每卖出一册，作者只可得0.6元，如果这些书全部卖光后，作者共获得26000元，问该书共印了多少册（）

A．36000

B．20000

C．30000

D．40000