若0<a<π2,0<β<π,且cosβ=-13,sin(α+β)=79,则sin

题型:选择题

问题:

0<a<
π
2
,0<β<π,且cosβ=-
1
3
sin(α+β)=
7
9
,则sinα等于(  )
A.
1
27
B.
5
27
C.
1
3
D.
3
27
考点:两角和与差的三角函数及三角恒等变换
题型:选择题

区位理论作为一种学说,产生于19世纪二三十年代,先后有______。

A.杜能的《孤立国对农业和国民经济之关系》

B.韦伯的《论工业的区位》

C.克里斯塔勒的中心地理论

D.李斯特的《行政区划论》

E.阿兰索的《孤立国》

题型:选择题

某地区有一口150米深的矿井,采矿工人发现在井底每年能见到两次阳光,此井最有可能位于 [ ]

A、回归线和南极圈之间

B、温带地区

C、南回归线和北回归线之间

D、寒带地区

题型:选择题

如果2001年广东省工业污染治理国家预算内资金为3.10亿元,那么2001-2003年,该项资金年平均增长率约为()。

A.75%

B.60%

C.50%

D.36%

题型:选择题

阅读理解。

     Last month, students from one hundred and three universities in eightyeight countries took part in

an international computer programming contest. The Battle of the Brains took place in Harbin, China. 

 __1__

     Jerry Cain, coach of Stanford University Team  California, says, "One of the programming problems

was trying to figure out how to break an arbitrary chocolate bar into a certain number of pieces of a

certain numb er of sizes and to do it as quickly as possible.    __2__"

     The students first listed the problems in order of difficulty.__3__ They designed ways to test their

solutions. And they wrote needed software systems.  Even the winning team from Shanghai Jiaotong

University in China was not able to solve all the problems within the given time limit.  Stanford's team

solved five problems and finished in the 14th place. Stanford was one of twentyone American universities

that took part in the contest this year.

     __4__ It began in 1970 at Texas A&M University. The contest quickly became popular in the

United States and Canada. It developed and grew as more and more schools took part in local and

area contests.

     The first final competition was held in 1977 at the Association for Computing Machinery Computer

Science conference. Today, a network of universities holds area competitions that send the winners to

the world finals, now organized by IBM. Contest spokesman Doug Heintzman says the world champions

receive prizes and scholarships.  __5__

A. The competitors show real interest in IBM.

B. Then they figured out the requirements of each.

C. And that's probably the simplest of all of them.

D. This competition is an opportunity to be recognized by famous universities from the world.

E. Threeperson teams from each school had five hours to solve eleven real world problems.

F. The official name of the Battle of the Brains is the ACM  International Collegiate Programming Contest.

G. They are also guaranteed an offer of employment with IBM.

题型:选择题

下列哪一项不能作为健康干预的优先项目考虑()。

A.白喉、麻疹的免疫接种

B.吸烟健康干预

C.流行性感冒的健康干预

D.高血压健康干预

E.以上都可作为优先项目考虑

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