下列关于简单算术股价平均数的说法正确的是( )。A．是以样本股每日最高价之和除以样

调整各个侧滚轮与导轨立柱管的间隙应为()毫米。

A、0.1

B、0.3

C、0.5

D、1.0

夜深人静，你即将进入梦乡。这时，如果有一只蚊子从你的耳边飞过，你就会听到一阵“嗡嗡”的声音。这种声音可不是从蚊子嘴里发出的，而是它在飞行时，翅膀迅速振动发出的。据科学家测试，蚊子在寻找目标飞行时，翅膀每秒钟能振动250～260次，这样引起的空气振动就是我们听到的蚊子的“叫声”了。

你能不能设计一个方案，探究蚊子飞行发出的声音从哪儿传来的？

The Maldives faces the threat of extinction from rising sea levels, but the government said on Thursday it was looking to the future with plans to build homes and a golf course that float.

An increase in sea levels of just 18 to 59 centimeters would make the Maldives -- a nation of tiny coral islands in the Indian Ocean -- virtually uninhabitable by 2100, the UN’s climate change panel has warned.

President Mohamed Nasheed has vowed a fight for survival, and last month he signed a deal with a Dutch company to study proposals for a floating structure that could support a convention centre, homes and an 18-hole golf course. “It is still early stages and we are awaiting a report on the possibility,” a government official said.

The company, Dutch Docklands, is currently building floating developments in the Netherlands and Dubai. There was no immediate comment from the firm but its website said it undertook projects that make “land from water by providing large-scale floating constructions to create similar conditions as on land”.

The Maldives began work on an artificial island known as the Hulhumale near the crowded capital island of Male in 1997 and more than 30,000 people have been settled there to ease congestion. The city, which has a population of 100,000, is already protected from rising sea levels by a 30-million-dollar sea wall, and the government is considering increasingly imaginative ways to combat climate change.

Nasheed, who staged the world’s first underwater cabinet meeting in October to highlight his people’s dilemma , has even spoken of buying land elsewhere in the world to enable Maldivians to relocate if their homes are flooded. He has also pledged the Hulhumale to turn his nation into a model for the rest of the world by becoming “carbon neutral” by 2020. His plan involves ending fossil fuel use and powering all vehicles and buildings from “green” sources.

1. What’s the main idea of the passage?

A. The Maldives plans to build floating homes for the rising sea level.

B. The Maldives’s president signed a deal with a Dutch company.

C. The Maldives staged the first underwater cabinet meeting.

D. The Maldives is considering ways to fight against the global warming.

2. Which statement is true about the Hulhumale?

A. The Hulhumale is a natural island near the capital of Male.

B. The Hulhumale is an artificial island to be built near the capital.

C. The Hulhumale was built in 1997 and has settled over 30,000 people.

D. The Hulhumale is protected by a 30-million-dollar sea wall.

3. According to the passage, the underlined word congestion means _______.

A. being endangered                     B. being crowded   

C. being flooded                        D. being disappearing

4. Which of the following is NOT Nasheed’s idea?_______

A. To purchase land elsewhere in the world to help Maldivians to relocate if their homes are flooded.

B. To make his nation a model for the rest of the world by becoming “carbon neutral” by 2020

C. To stop using fossil fuel and power all vehicles and buildings from “green” sources.

D. To build more artificial islands for people to settle there.

5. We can infer from the passage that ________.

A. By 2100, all the the Maldives will live on artificial islands.

B. The plans to build homes and a golf course that float have been carried out

C. Maldive has been greatly affected by the global warming.

D. . Dutch Docklands is the president of Maldive.

微生物发酵工程发酵产物的类型主要包括（）。

A、产物是微生物菌体本身

B、产品是微生物初级代谢产物

C、产品是微生物次级代谢产物

D、产品是微生物代谢的转化产物

E、产品是微生物产生的色素

正常情况下，由以下3个系统维持机体在空间的平衡，即( )、( )和( )o