阶梯价格指令是指按指定的价格间隔，逐步购买或出售指定数量期货合约的指令。买入时采取阶

    Do you scream on a roller coaster ride? You slowly climb up a steep slope until an almost vertical(垂直的) drop, and then... Ahhhhhhhh! Thrill-seekers like me are in luck because theme parks are pushing the boundaries of technology to create the fastest, tallest, scariest roller coasters the world has ever known.

Alton Towers in Britain opened the world's first 14-1oop roller coaster a few months ago, called The Smiler. Over in Abu Dhabi, Ferrari World claims to have the world's fastest one. Ferrari World's Formula Rossa ride sends out passengers from 0-240km/h in just 4. 9 seconds. During this rapid acceleration they experience G-forces only fighter pilots usually  feel: Up to 4. 8G. The designer of several rides at Alton Towers, said: "While we can stand 6-8Gs for very short periods of  time, ff we experience 5G for more than five seconds we're likely to "black out."

On modern roller coasters passengers experience about 3G in tight turns and loops. But while we may have reached the limit in terms of G-forces, there is no technological limit to how fast or how high roller coasters can go---it's all down to money. Alton Towers' The Smiler cost ~18m to build.

Some companies are finding other ways to keep us amused. There's a move towards indoor rides where the experience is improved by audio-visual technologies. For example, a company called Dynamic Structures is currently developing a "coal-mine-themed" ride for a client in Dubai that will combine speed and G-forces with 3D projection effects and robotics, which will trick your brain into thinking you're really falling.

I can't wait to enjoy this one. What about you: Do you like being upside down?

小题1:The underlined phrase "black out" in the second paragraph probably means  ....  .

A．stop breathing

B．lose consciousness for a short time

C．lose memory forever

D．bleed to death小题2: We can learn from the passage that __

A．all the theme parks are creating the fast roller coasters

B．the Smiler sends out passengers from 0-240km/h in just 4.9 seconds

C．it is unusual for fighter pilots to feel up to 4.8G

D．the more the money is spent, the faster the roller coaster can go小题3: The feature of the "coal-mine-themed" ride is

A．3Dtechnologies

B．indoor rides

C．G-forces

D．dynamic structures小题4: What is the best title for the passage?

A．The Fastest Roller Coaster

B．The Smiler and G-forces

C．Screaming for Fun

D．The New Technology

 海带中含有丰富的碘。为了从海带中提取碘，某研究性学习小组设计并进行了以下实验。

请填写下列空白：   

（1）步骤①灼烧海带时，除需要三脚架外，还需要用到的实验仪器是____________（从下列仪器中选出所需的仪器，用标号字母填写在空白处）。

A.烧杯    B.坩埚  C.表面皿   D.泥三角  E.酒精灯  F.干燥器

（2）步骤③的实验操作名称是____________；步骤⑥的目的是从含碘苯溶液中分离出单质碘和回收苯，该步骤的实验操作名称是___________。

（3）步骤④反应的离子方程式是 ______________。   

（4）步骤⑤中，某学生选择用苯来提取碘的理由是_____________ 。  

（5）请设计一种检验提取碘后的水溶液中是否还含有单质碘的简单方_____________。

咬合干扰不包括（）

A.正中咬合干扰

B.前伸咬合干扰

C.工作侧咬合干扰

D.非工作侧咬合干扰

E.正中关系咬合干扰

女，45岁，有心肌缺血病史，经治疗后几年来一直健康。近日突然出现心慌，气短，数分钟后能自然缓解，如此，每日可发作数次，发作时常伴有心绞痛的症状。经心电图检查认为阵发性室上性心动过速，此时最好选用（）

A.普鲁卡因胺

B.硝苯地平

C.维拉帕米

D.索他洛尔

E.普罗帕酮

常见的基于页面的信息集成工具有（）

A、Word

B、FrontPage

C、Flash

D、Authorware