已知函数f(x)=x2-2tx+1,x∈[2,5]有反函数,且函数f(x)的最大

题型:解答题

问题:

已知函数f(x)=x2-2tx+1,x∈[2,5]有反函数,且函数f(x)的最大值为8,求实数t的值.

考点:函数的奇偶性、周期性二次函数的性质及应用
题型:解答题

常用的消毒碘液浓度为()

A.0.125%

B.0.25%

C.1.25%

D.2.5%

E.5%

题型:解答题

阅读理解。

     There are more than one billion people around the world who smoke. Bill Gates, cofounder

and former CEO of Microsoft, wants them all to quit. So does New York City's mayor Michael

Bloomberg. This week, the Gates Foundation, a charity organization set up by Bill Gates and his

wife, Melinda, teamed up with Bloomberg to donate $500 million over the next five years to

antitobacco programs.

     Bloomberg is no stranger to antitobacco plans. He has been fighting tobaccouse in New York

City for years. In 2002, Bloomberg pushed for a ban on smoking in all New York City restaurants.

     Bloomberg's Initiative to Reduce Tobacco Use was created in 2005.  It aims to discourage

smoking trends around the world by working to change tobacco's image, protect nonsmokers from

secondhand smoke, and help people quit. Bloomberg gave $ 125 million to start the program. Now,

he is adding another $ 250 million. The Gates Foundation will invest $ 125 million over five years to

fight the tobacco epidemic, including a $ 24 million gift directly to the Bloomberg Initiative.

     The money donated by the Gates Foundation will support antismoking efforts in developing

countries where tobacco use is the highest. "Tobaccocaused diseases have become one of the

greatest health challenges facing developing countries," Gates says. In addition to donating to the

Bloomberg Initiative, the Gates Foundation will also help prevent the tobacco epidemic from taking

root in Africa. "The epidemic in Africa is not well advanced," Gates explains. "That means that we

can catch it at an early stage."

     Tobaccouse kills more than five million people every year. If the trend doesn't change, more than

one billion people could die of tobaccorelated illnesses this century. Gates and Bloomberg have high

hopes to change these statistics. "Together we can make a clear, measurable difference, not just for

ourselves and our generation, but for the generations that come after us," says Bloomberg.

1. The passage is mainly about ________. 

A. the harmful effects of smoking

B. Bill Gates' contribution to the world

C. a ban on smoking in New York City

D. a plan to stop smoking

2. How much does Bloomberg invest altogether? 

A.  $ 125 million.  

B.  $ 250 million.

C.  $ 375 million.  

D.  $ 500 million.

3. We learn from the passage that ________. 

A. the Gates Foundation is set up by Bill Gates and Bloomberg

B. tobaccouse has become a big threat to developing countries

C. Bloomberg's Initiative to Reduce Tobacco Use was created in 2002

D. tobaccouse kills more than fifty million people every year

4. What's Gates and Bloomberg's attitude towards the antismoking efforts? 

A. Optimistic.                  

B. Skeptical.

C. Opposable.                  

D. Surprised.

题型:解答题

流动人口育龄夫妻生育第一个子女的,()在现居住地的乡(镇)人民政府或者街道办事处办理生育服务登记。

A、不能

B、应当

C、可以

题型:解答题

治阳气衰脱,大汗淋漓,气促喘息者,应首选的药物是()

A.附子、干姜

B.附子、人参

C.附子、肉桂

D.附子、桂枝

E.附子、白术

题型:解答题

粗加工多头蜗杆时,一般使用()卡盘。

A.偏心

B.三爪

C.四爪

D.专用

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