已知数列{an}的前n项为和Sn,点(n,Snn)在直线y=12x+112上.数

题型:解答题

问题:

已知数列{an}的前n项为和Sn,点(n,
Sn
n
)
在直线y=
1
2
x+
11
2
上.数列{bn}满足bn+2-2bn+1+bn=0(n∈N*),且b3=11,前9项和为153.
(Ⅰ)求数列{an}、{bn}的通项公式;
(Ⅱ)设cn=
3
(2an-11)(2bn-1)
,数列{cn}的前n和为Tn,求使不等式Tn
k
57
对一切n∈N*都成立的最大正整数k的值.
(Ⅲ)设f(n)=
an(n=2l-1,l∈N*)
bn(n=2,l∈N*).
是否存在m∈N*,使得f(m+15)=5f(m)成立?若存在,求出m的值;若不存在,请说明理由.
考点:数列求和的其他方法(倒序相加,错位相减,裂项相加等)
题型:解答题

如图所示为我国南方部分地区图,回答下列问题.

(1)①是我国最大的水利工程______,该水利工程的主要作用是______.

(2)贵阳是我国著名的“夏都”(避暑胜地),主要原因是什么?

(3)台湾省的火烧寮年平均降水量达6000多毫米,称为“中国的雨极”,从地形因素分析原因.

(4)简述珠江三角洲对外开放的有利条件.

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海洋是一个丰富的资源宝库,通过海水的综合利用可获得许多物质供人类使用。

(1) 海水中盐的开发利用:

Ⅰ.海水制盐目前以盐田法为主,建盐田必须选在远离江河入海口,多风少雨,潮汐落差大且又平坦空旷的海滩。所建盐田分为贮水池、蒸发池和_______池。

II.目前工业上采用比较先进的离子交换膜电解槽法进行氯碱工业生产,在电解槽中阳离子交换膜只允许阳离子通过,阻止阴离子和气体通过,请说明氯碱生产中阳离子交换膜的作用____________________________________________。(写一点即可)

(2)电渗析法是近年来发展起来的一种较好的海水淡化技术,其原理如下图所示。请回答后面的问题:

Ⅰ.海水不能直接通入到该装置中,理由是_____________________________________________。

Ⅱ. B口排出的是________(填“淡水”或“浓水”)。

(3)用苦卤(含Na+、K+、Mg2+、Cl-、Br-等离子)可提取溴,其生产流程如下:

Ⅰ.若吸收塔中的溶液含BrO3,则吸收塔中反应的离子方程式为_____________

_________________________________________。

Ⅱ.通过①氯化已获得含Br2的溶液,为何还需经过吹出、吸收、酸化来重新获得含Br2的溶液?_____________________________________________________________________。

Ⅲ.向蒸馏塔中通入水蒸气加热,控制温度在900C左右进行蒸馏的原因是___________________________________________________________________________。

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阅读理解。

     Five years ago, David Smith wore an expensive suit to work every day. "I was a clothes addict," he

jokes. "I used to carry a fresh suit to work with me so I could change if my clothes got wrinkled." Today

David wears casual clothes-khaki pants and sports shirt-to the office. He hardly ever wears a necktie.

"I'm working harder than ever," David says, "and I need to feel comfortable."

      More and more companies are allowing their office workers to wear casual clothes to work. In the

United States, the change from formal to casual office wear has been gradual. In the early 1990s, many

companies allowed their employees to wear casual clothes on Friday, but only on Friday. This became

known as "dress-down Friday" or "casual Friday". "What started out as an extra one-day-a-week benefit

for employees has really become an everyday thing." said business consultant Maisly Jones.

     Why have so many companies started allowing their employees to wear casual clothes? One reason is

that it's easier for a company to attract new employees if it has a casual dress code. "A lot of young people don't want to dress up for work," says the owner of a software company, "so it's hard to hire people if you have a conservative dress code." Another reason is that people seem happier and more productive when

they are wearing comfortable clothes. In a study conducted by Levi Strauss Company, 85 percent of

employers said that they believe that casual dress improves employee morale(士气). Only 4 percent of

employers said that casual dress has a negative effect on productivity. Supporters of casual office wear

also argue that a casual dress code helps them save money. "Suits are expensive, if you have to wear one

every day," one person said. "For the same amount of money, you can buy a lot more casual clothes."

1. David Smith refers to himself as having been "a clothes addict," because          .  

A. he often wore khaki pants and a sports shirt

B. he couldn't stand a clean appearance

C. he wanted his clothes to look neat all the time

D. he didn't want to spend much money on clothes

2. David Smith wears casual clothes now, because           .  

A. they make him feel at ease when working

B. he cannot afford to buy expensive clothes

C. he looks handsome in casual clothes

D. he no longer works for any company

3. According to this passage, which of the following statements is FALSE?  

A. Many employees don't like a conservative dress code.

B. Comfortable clothes make employees more productive.

C. A casual clothes code is welcomed by young employees.

D. All the employers in the U.S. are for casual office wear.

4. According to this passage, which of the following statements is TRUE?    

A. Company workers started to dress down about twenty years ago.

B. Dress-down has become an everyday phenomenon since the early 1990s.

C."Dress-down Friday" was first given as a favor from employers.

D. Many workers want to wear casual clothes to impress people.

5. In this passage, the following advantages of casual office wear are mentioned except        .    

A. saving employees' money

B. making employees more attractive

C. improving employees' motivation

D. making employees happier

题型:解答题

案例1:某县政府发布《关于规范药品零售市场的通告》,规定新开零售药店须与原有零售药店相距400米以上。外地某药品经营公司经药监部门批准到该县一老药店附近筹建新药店,老药店依据县政府通告予以阻止,双方为此闹得不可开交。案例2:某市政府印发“燃气管理规定”,规定燃气燃烧器具安装、维修单位须经建设部门进行资质审查,发给《燃气燃烧器具安装维修资质证书》,并规定对该资质证书实行年检。
在上述案例中,“红头文件”存在的问题是( )。

A.前例部门争权,红头文件开道;后例发文给自己授权
B.前例随意干涉民事关系;后例上级文件出政策,下级文件出对策
C.前例市政府都无权发的“罚款文件”,乡政府发了;后例“红头文件”明目张胆地强买强卖
D.前例乡政府发个文件,就伸手收钱;后例用“红头文件”为本地市场“扎篱笆”

题型:解答题

下列哪些账表簿不可以补打()

A.科目日结单

B.科目统驭单

C.机构轧账单

D.柜员轧账单

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