某民事诉讼案开庭审理时，原告王某临时申请审判长回避，根据民事诉讼法及相关规定，人民法

用一根长为l的丝线吊着一质量为m带电荷量为q的小球，小球静止在水平向右的匀强电场中，如图所示，丝线与竖直方向成37⁰角．现突然将该电场方向变为向下但大小不变，不考虑因电场的改变而带来的其他影响（重力加速度为g），求：

（1）匀强电场的电场强度的大小？

（2）电场方向变为向下小球经过最低点时的瞬时速度多大？

（3）电场方向变为向下小球经过最低点时丝线对小球的拉力多大？

Questions from 31 to 35 are based on the following passage:

　　The exporter, as drawer of a draft (bill of exchange), hands the draft to his bank, the remitting bank, who in turn forwards it to the buyer through a collecting bank in the buyer’s country. A draft (also called a bill) is a written order to a bank or a customer to pay someone on demand or at a fixed time in the future a certain sum of money. If shipping documents accompany the draft, the collection is called “documentary collection.”

　　Documentary collection falls into two major categories: one is documents against payment(D/P); the other, documents against acceptance (D/A).

　　Documents against payment, as the term suggests, is that the collecting bank will only give the shipping documents representing the title to the goods on the condition that the buyer makes payment.

　　Where the paying arrangement is D/A, the collecting bank will only give the buyer the shipping documents after buyer’s acceptance of the bill drawn on him, i.e. the buyer signs his name on the bill promising to pay the sum when it matures. In return he gets what he needs – the shipping documents.

　　Under D/A, the seller gives up the title to the goods – shipping documents before he gets payment of the goods. Therefore, an exporter must think twice before he accepts such paying arrangement.

The meaning of D/A is（）.

A．documents against acceptance

B．documents against payment

C．delivery after payment 　　

D．cash against payment

（9分） 如图所示，一圆柱形绝热容器竖直放置，通过绝热活塞封闭着摄氏温度为t₁的理想气体，活塞的质量为m，横截面积为S，与容器底部相距h₁。现通过电热丝给气体加热一段时间，使其温度上升到（摄氏）t₂，若这段时间内气体吸收的热量为Q，已知大气压强为p₀，重力加速度为g，求：

(1)气体的压强．

(2)这段时间内活塞上升的距离是多少？

(3)这段时间内气体的内能如何变化，变化了多少？

根据汉语完成句子。  

1. People in Colombia                   (宽松的) time.  

2. It's okay if you arrive____           (晚一点)．  

3. We usually              (计划) visit our friends.  

4. It's very important                 (准时) in Switzerland.

对原发性肝癌早期诊断最有价值的是（）。

A．甲胎蛋白测定

B．癌胚抗原测定

C．B超检查

D．CT检查

E．腹部平片