冷却液冷却常数是指（）时，冷却液出口温度与环境温度的差值。

阅读下列材料：

材料一 经济外交是关系到国家经济发展，关系到国家政治、经济和安全利益，关系到国际经济协调、世界和平与经济可持续发展的外交政策和行为。经济发展了才使国家的政治安全得以维护，而一国的经济外交，对本国的经济发展十分重要。

——周永生《经济外交》

材料二 近年来，随着我国经济实力增强、政治影响力扩大和对外开放水平提高，我与外部世界的经济联系和互动明显加强，与发展中国家关系也步入一个新阶段。当前……国际政治经济格局发生深刻变化，注重经济外交成为各国的共同选择。在变革中，发展中国家整体实力有所增强，国际影响力不断加大，对建立国际政治经济新秩序抱有强烈愿望。发展中国家人口众多，发展潜力巨大，与我国的经济互补性很强，与我发展经贸合作的要求十分迫切。作为发展中大国，我国与发展中国家没有根本利害冲突。

——人民日报社论《对发展中国家经济外交大有可为》(2004年9月3日)

材料三 1998年中央提出“要抓紧研究和实施‘走出去’的开放战略，积极开拓国际市场和利用国外资源，以利增加我国经济发展的动力和后劲”。……新的国内外形势要求政府对“走出去”战略的目标、内涵予以明确构筑，赋予新内涵，并出台新的支持性政策措施，以便在新一轮国际产业转移大潮中，为我国谋求更大的经济增长动力和发展空间。

——邢厚媛《国际商报》

请回答：

(1)依据材料一归纳经济外交的基本特征。（3分）

(2)结合材料二和所学知识说明20世纪90年代国际政治经济格局发生的变化，分析我国对发展中国家开展经济外交的有利因素。（6分）

(3)21世纪以来，我国在经济外交上实行“走出去”战略。为此，我国政府采取了哪些重要举措?与此相适应，我国经济体制出现了什么重大变化?（3分）

为测定木块与斜面间的动摩擦因数，某同学让木块从斜面上端自静止起做匀加速下滑运动(如图所示)，他使用的实验器材仅限于：①倾角固定的斜面(倾角未知)；②木块；③秒表；④米尺．实验中应记录的数据是________，计算动摩擦因数的公式是=__________，为了减小测量的误差，可采用的办法是___________________．

（二）2003年某国有低压电器厂的财会机构负责人于某由于工作调动，该厂厂长刘某任命他的好友、刚刚取得会计从业资格证书的行政科李某为新的财会机构负责人，按照规定办理交接后于某调离该厂。李某为报答厂长刘某的知遇之恩，将刘某刚刚中专财会毕业、没有会计从业资格证书的女儿招聘到厂里担任出纳工作，并负责往来款项账簿的登记工作。同年，该厂出租闲置厂房一处，取得租赁收入150万元，厂长刘某暗示李某此笔收入可不入账，留作厂领导交际应酬和年终发放奖金。随即，李某指派会计人员张某办理此事，张某提出反对意见，坚持将此笔收入入账，并按规定缴纳各项税金。厂长刘某为了达到目的，将会计人员张某调离财会机构下放到车间。 2004年末，该厂年终预计亏损80万元。为了完成上级主管部门下达的利润指标，厂长刘某授意李某将应计入2004年度的部分费用挂在长期待摊费用科目，待今后企业经营形势好转再计入成本费用。经过调整，该厂对外报出的2004年度财务会计报告反映的利润额为180万元，超额30万元完成利润指标。 2005年初，审计部门接到举报信后进驻该厂进行审计。厂长刘某为了防止“小金库”等问题的败露，指使李某销毁有关“小金库”的会计资料。经过审计部门的严格审计，发现了该厂的上述问题并加以证实，据此给予相关人员处分。 要求：请根据上述事项回答下列问题。

该厂厂长刘某任用行政科李某为财会机构负责人，这种行为违反了（）。

A．《会计法》关于从事会计工作的人员，必须取得会计从业资格证书的规定

B．《会计基础工作规范》关于会计人员回避制度的规定

C．《会计法》关于担任单位会计机构负责人（会计主管人员）的，应当具备会计师以上专业技术职务资格或者从事会计工作三年以上经历的规定

D．《会计专业职务试行条例》关于会计专业职务聘（任）用的规定

阅读理解。

    Surveys of American teenagers find that about half of them do not get enough sleep on school nights. They

get an average of 60 to 90 minutes less than experts say they need. 

    One reason for this lack of sleep is biology. Experts say teens are biologically programmed to go to sleep

later and wake up later than other age groups. Yet many schools start classes as early as seven in the morning.

As a result, many students go to class feeling like sixteen-year-old Danny. He plays two sports, lacrosse and

football. He is an active teen-except in the morning.

    DANNY:"Getting up in the morning is pretty terrible. I'm just very out of it and tired. And then going to

school I'm out of it, and through first and second period I can barely stay awake.

    "Michael Breus is a clinical psychologist with a specialty in sleep problems. 

    Teens, he says, now commonly sleep for only 6.5 hours to 7 hours. He says sleepy teens can experience

a form of depression (压抑) that could have big effects on their general well-being. It can affect not just their

ability in the classroom but also on the sports field and on the road. 

    So what can schools do about sleepy students? The psychologist says one thing they can do is start classes

later in the morning. Eric Peterson is the head of St. George's School in the northeastern state of Rhode Island.

He wanted to see if a thirty-minute delay would make a difference. It did. 

    He says visits to the health center by tired students decreased by half. Late arrivals to first period fell by a

third. And students reported that they were less sleepy during the day. 

    Eric Peterson knows that changing start times is easier at a small, private boarding school like his. But he is

hopeful that other schools will find a way. 

    Patricia Moss, an assistant dean at St. George's School, says students were not the only ones reporting

better results. 

    PATRICIA MOSS:"I can say that generally all the teachers noticed immediately that kids were happier to be

there at eight-thirty than they were at eight."

1. According to experts like Michael Breus, how many hours of sleep should teens get every day? [ ]

A. 6.5 hours to 7 hours

B. at least 7.5 hours

C. More than 9 hours

D. Less than 7 hours

2. According to some experts, why do teens wake up later than adults?

A. Because they are lazier.

B. Because they need more sleep.

C. Because they are biologically programmed to sleep late and wake up late.

D. Because they play sports.

3. The article mentions the story of sixteen-year-old Danny to _____.

A. show how he hates getting up in the morning.

B. show how teens can be affected by a lack of sleep.

C. show how he turns from an active boy to a tired school child.

D. show how teens hate school.

4. What does Eric Peterson do about the problem of sleepy students?

A. He visits the health center.

B. He punishes late students.

C. He punishes sleepy students.

D. He starts his school time 30 minutes later.

5. Which of the followings is not true according to the article?

A. Later school time leads to fewer late arrivals.

B. Er ic Peterson’s experiment h as answered his question.

C. The writer of this article seems to support later school time.

D. Teachers of St. George’s School don’t seem to support later school time.

《论学问》中认为数学使人（）？

A.巧慧

B.深沉

C.善辩

D.精细