先化简再求值：（I）求3x2y-[5xy2+2(x2y-12)+x2y]+6xy

(12分)如图所示，AB、CD两金属板间形成一匀强电场(板的边缘电场不考虑)，板长为L，电场强度为E。一质量为m，电荷量为+q的粒子（不计重力）沿两板的中间线OO′从AC中点O处以初速度v₀射入匀强电场，粒子恰好能从极板边缘上的D点射出匀强电场。求：

（1）小球在匀强电场中的运动时间；

（2）两板间距离d；

（3）若要使粒子打在CD板的正中央P点，现调节粒子的入射速度大小变为v′，方向不变, v′与v₀的比值为多少？

按作用机理分，地基处理主要有哪些？

我国古代编纂规模最为浩繁、涉及范围最广泛的类书是( )。

A．《艺文类聚》

B．《四库全书》

C．《永乐大典》

D．《洪武正韵》

单词拼写

小题1:If you can swim a        the river, I’ll be waiting for you on the other side.

小题2:She took part in helping people in the Wenchuan Earthquake. She would never forget this unusual      .

小题3:I like c      with my friends online very much.

小题4:In Lily’s paper there are f           mistakes than in Jack’s.

小题5:I read my essay a          in class and everyone can hear me clearly.

小题6:His speech was boring, but he did not r           it.

小题7:He is good at thinking. I think he can answer the question in a d            way.

小题8:Would you mind not w          your time?

小题9:Don’t stay up late, or you will feel s             in class during the day.

小题10:He joined the army(军队) five years ago, so he has been a s              for five years.

己内酰胺生产工艺中，闪蒸槽压力高对成品质量没有影响。