对老窑有图纸时，探水线一般由积水线外推（）米以上。A、30m B、50m C、60m D、

制备纳米薄膜装置的工作电极可简化为真空中间距为d的两平行极板，如图甲所示，加在极板A、B间的电压U_AB作周期性变化，其正向电压为U₀，反向电压为-kU₀（k＞1），电压变化的周期为2r，如图乙所示．在t=0时，极板B附近的一个电子，质量为m、电荷量为e，受电场作用由静止开始运动．若整个运动过程中，电子未碰到极板A，且不考虑重力作用．

（1）若k=

5

4

，电子在0-2r时间内不能到达极板A，求d应满足的条件；

（2）若电子在0～200t时间内未碰到极板B，求此运动过程中电子速度v随时间t变化的关系；

（3）若电子在第N个周期内的位移为零，求k的值．

Shanghai: Car rentals (出租)are becoming more and more popular as an inexpensive way of taking to roads. Business people, foreign and families alike are making good use of the growing industry.

The first car rental firm opened in Shanghai in 1992 an dnow 12 car rental players are in the game, with more than 11,500 cars in their books.

The largest player-Shangha Bashi Tourism Car Rental Center offers a wide variety of choices-deluxe sedans, minivans, station wagons, coaches. Santana sedans are the big favorite.

Firms can attract enough customers for 70 percent of their cars every month. This fighure shoots up during holiday seasons like National Day, Labor Day and New Year’s Day, with some recording 100 percent rental.

The major market force rests in the growing population of white-collar employees (白领雇员), who can afford the new service, said Zhuang Yu, marketing manager of Shanghai Angel Car Rental Co.

小题1:The words “deluxe sedans, ” “minivans” and “station wagons” used in the text refer to_________.

A．cars in the making

B．car rental firms

C．cars for rent

D．car makers小题2: Which of the following statements is true according to the text?

A．70% of the cars can be rented out on holiday.

B．70% of the customers are white-collar employees.

C．More firms are open for service during holiday seasons.

D．Some firms rent out all their cars during holiday seasons.小题3:Shanghai’s car rental industry is growing so fast mainly due to_________.

A．better cars supplied by producers

B．fast service offered by car rental firms

C．the increasing number of white-collar employees

D．people’s growing interest in traveling during holidays

下列关于液体制剂特点的表述，正确的是（）

A.不能用于皮肤、黏膜和人体腔道

B.药物分散度大，吸收快，药效发挥迅速

C.液体制剂药物分散度大，不易引起化学降解

D.液体制剂给药途径广泛，易于分剂量，但不适用于婴幼儿和老年人

E.某些固体制剂制成液体制剂后，生物利用度降低

男性45岁，慢性支气管炎15年，呼吸困难突然加重一天，伴右侧胸痛。查体：发绀，桶状胸，右肺呼吸音减低，左肺散布干啰音，心浊音界缩小，剑突下可触及收缩期搏动，考虑诊断为（）

A.慢性支气管炎、肺气肿、肺部感染

B.慢性支气管炎、肺气肿、早期肺心病、右侧气胸

C.慢性支气管炎、肺气肿、右侧气胸

D.慢性支气管炎、肺气肿、早期肺心病、右侧胸腔积液

E.慢性支气管炎、肺气肿、右侧胸腔积液

PWS不可以运行在（）环境下。

A.winDows98

B.winDowsNT

C.MAC/os

D.winDows95