生态系统的环境组分包括（）。A、辐射 B、大气（气体） C、生物 D、水体 E、土体

A tsunami (海啸) happened in some southern Asian countries _____ December, 2004.[ ]

A. at    

B. on  

C. in  

D. by

A person searches various websites for different reasons, such as school, work, or entertainment. For teenagers, many informative resources on the Internet can be used. As a matter of fact, there are educational, music and art websites that are truly helpful to teenagers, because they can help make one’s life easier.

Educational websites are helpful to a teenager in doing school work and searching for a college. Some can help studying for tests, explaining a lesson, and doing homework. Some can help find the right schools based on one’s interests. And still others have pages devoted to the social life at each of the colleges or the specific activities that occur at a certain school.

Some free music sites enable a teenager to diversify their musical tastes. On these sites, all types of music are available such as pop, cock, jazz, and country. One can type in a song, category or artist and his or her entire catalog appears. Then, the listener can make multiple playlists without creating an account(账户)with the site.

There are various art websites that can help students to appreciate and create art pieces. On these sites, a student can view numerous photos and art pieces from different mediums or create an account with the website to upload them art pieces for people to see. In addition, one can enjoy various art projects that people have created on display for the rest of the world.

Truly informative resources are offered on the Internet. The best suggestion one car receive is to try to look for new websites that can help in the educational, music, or art area so one can become well-rounded and informed.

Truly Helpful Websites for Teenagers

工业企业的质量成本一般包括（）

A.外部质量损失

B.质量预防费用

C.内部质量损失

D.评价质量费用

如客户发生重大变故，农村信用社有权提前取消客户信用等级。重大影响事件包括但不限于（）。

A.申请人死亡

B.丧失民事行为能力

C.失去稳定收入来源

D.发生不良贷款

E.超出自身还款能力的担保

价值管理工作过程首先要做的是（）

A.信息收集

B.方案创造

C.方案评价

D.方案提交