简述灭菌的方法。

选择性培养基在培养基中加入抑制剂，目的是抑制标本中的非目的菌生长。

护士进行操作，手、眼、耳并用属于

A．注意的范围性

B．注意的稳定性

C．注意的分配性

D．注意的转移

E．有意注意

阅读理解。

      As a boy growing up on a farm near the Caribbean coast of Colombia(哥伦比亚), Alvaro

Cogollo loved both plants and vallenato, the traditional music of the region.As a biology student

in the 1970s, Cogollo traveled around the country to document its rich botanical heritage and,

informally, studied the music that tells an important story of Colombia.

     "We were colonized by the Spanish; later, Africans were brought as slaves to exploit gold

mines; and the native peoples were already here," he says."That is what authentic vallenato

represents with its three instruments: the accordion(手风琴), from a European origin; la caja drum,

which is of African origin; and la guacharaca, a beating instrument made from a palm tree, which is

from native American origin."

     Over the course of his nearly four-decade career, Cogollo has discovered more than 150 new

species of plants, 17 of which bear his name.Although Cogollo never earned a PhD, his colleagues

say he's made invaluable contributions to knowledge of Colombia's plant at a time when deforestation

(砍伐森林) is a big threat to the country' s biodiversity.Governments have focused on trying to move

 the country out of poverty and conflict through exploiting its natural resources, not through scientific

resource development.But Cogollo sees things a different way.By educating the public about alternative

uses for the land, and researching plants' potential uses-including as medicines, foods, and bio-fuels-

Golombia could improve its economy and quality of life without neglecting conservation, Cogollo says.

     Cogollo's other major achievement has been the transformation of a neglected botanical garden in a

Medellm neighborhood into a well-known center for research, environmental education, and community

gatherings.What had been a club for wealthy orchid enthusiasts now offers free admission and attracts

rich and poor alike.The success of the botanical garden has in turn contributed to the transformation

of Medellm.Once seriously damaged, by violent wars between armed groups, the city has had some

improvements that include better public safety, tougher pollution controls and the creation of green

spaces.

     What Cogollo has focused his latest efforts on is teaching Colombians from all social classes and

backgrounds about the importance of biodiversity and conservation through a shared musical heritage.

"The fact that Alvaro's been able to give talks to audiences filled with all kinds of people is very

important, and that's what happened in Medellm the first time he talked about vallenato music,"

Dr.Forcro says."People sitting there had no idea of environmental conservation, and then they did."

1. What's the main feature of vallenato music?

A. It records the history of Colombia．

B. It sounds like the voice of plants．

C. It plays with local instruments．

D. It has origins from all over the world．

2. While protecting the environment, Cogollo attached importance to ___．

A. the research of music

B. the protection of plants

C. the improvement of people's life

D. the communication with different people

3. The purpose of rebuilding the botanical garden is ____．

A. to raise the public's environmental consciousness

B. to set up a club for rich orchid enthusiasts

C. to give talks about vallenato music

D. to create a fair economic system

4. People from different backgrounds came to Cogollo's reports about biodiversity mainly because

of      .

A. their common interest in Vallenato music

B. their improved environmental consciousness

C. his popularity in environmental protection

D. his previous achievements in the city development

下列物质中含有非极性键的共价化合物是                          （   ）

A．H₂O₂

B．CH₄

C．Na₂O₂

D．I₂

自产自用应税产品，其纳税义务发生时间为移送使用应税产品的（）。

A.次日

B.10日后

C.1个月后

D.当天