俗话说：一个篱笆三个桩，一个好汉三个帮。你对这句话的理解是[ ] A．朋友就是用

结合首字母提示完成短文。

      Mark Twain is a   1    American writer. One day, he wanted to go to Dijon by train. He was very tired,

so when he was on the train, he asked the conductor to w 2   him up when they arrived in Dijon. He told

him that he was a very h 3   sleeper, and if he couldn't wake him up, just to keep on trying. Then Mark

Twain went to sleep. When Mark Twain woke up, he was a  4    in Paris. He was very angry. The conductor

had made a mistake and put another American i 5   of Mark Twain off the train in Dijon.

贴水出售的债券的到期收益率与该债券的票面利率之间的关系是（）。

A.到期收益率等于票面利率

B.到期收益率小于票面利率

C.到期收益率大于票面利率

D.无法比较

下列各组词语中划线的字的读音，与所给注音全都相同的一组是  (     )

A．解 jiě解决押解解释解数

B．宿sù宿舍宿营宿命归宿

C．恶wù厌恶恶心恶习恶劣

D．差chā差错误差出差差距

数字版权管理(DRM)主要采用数据加密、______、数字水印和数字签名技术。

A．版权保护

B．认证技术

C．防篡改技术

D．访问控制技术

啤酒发酵中，双乙酰是如何形成的？怎样控制？