化简求值: (1)2a﹣5b+3a+b; (2)2(3x2﹣2xy)﹣4(2x2

题型:计算题

问题:

化简求值: (1)2a﹣5b+3a+b;

(2)2(3x2﹣2xy)﹣4(2x2﹣xy﹣1);

(3)5(3a2b﹣ab2)﹣4(﹣3ab2+2a2b),其中a=﹣2,b=3;

(4)已知a、b互为相反数,c、d互为倒数,m是绝对值等于3的负数,求m2+(cd+a+b)×m+(cd)2008的值.

(5)已知a+b=4,ab=﹣2,求代数式(4a﹣3b﹣2ab)﹣(a﹣6b﹣ab)的值.

考点:整式的加减相反数绝对值倒数代数式的求值
题型:计算题

在技术创新中,内企业家区别于企业家的根本之处是()。

A.内企业家可自主决策

B.内企业家活动局限在企业内部,受多因素制约

C.内企业家不需征得所在企业的认同和许可

D.内企业家可选择自己认为有价值的机会

题型:计算题

125+81+75=81+(125+75)这里应用 了[ ]

A.加法交换律 

B.加法结合律

C.加法交换律和结合律

题型:计算题

根据以下资料,回答第43—45题。高科技离人民大众的日常生活到底有多远,这取决于科普工作者的努力程度。无论是科普创作还是科普宣传,都要求从业者不仅应具备足够的科学技术知识,还应具 备以普通民众能理解的语言方式来表达的文字能力。要同时具备这两个条件就意味着,科普的创作与传播是一项专业性较强的工作,而非一般的科技专业人员或一般 的文字工作者所能胜任。鉴于此,倡仪大学开设科普专业,理、工、农、医均可设置本行业的科普专业。科普专业不以艰深为追求目标,而以科普创作和科普宣传为 方向,所培养的是宽口径的“杂家”,属于文理跨学科专业,需要招收和培养的是跨学科人才,如理科类科普专业应在数、理、化、天、地、生中至少选学2至3门 为主课,又如工科类科普专业则应涉及机械、电子、计算机、建筑、通讯、环保等多门专业。总之,科普专业的培养目标不是单一学科的纵向深入,而是多门学科的 横向普及。科普专业的就业方向主要有出版社、杂志社、报社、电视台、广播电台、学校、社区等等,另外,还可为科普创作及科普宣传工作者设置专门的组织机 构、研究中心。显而易见,大众媒介掌握着科学普及所需要的最有利的工具。从全面提高我国民众科学素质的角度看,电视台和广播电台都应大量开设面向儿童及成 人的科普专题节目。

从上文可以得知,科普专业的最大特点是()。

A.以科普宣传为方向

B.专业面广

C. 需要一定的文字功底

D.不以艰深为追求目标

题型:计算题

阅读理解。

    Parents often believe that they have a good relationship with their teenagers (青少年). But last summer,

Joanna and Henry noticed a change in their elder son: suddenly he seemed to be talking far more to his friends

than to his parents. "The door to his room is always shut." Joanns noted.

    Tina and Mark noticed similar changes in their 14-year-old daughter. "She used to cuddle up (蜷伏) with

me on the sofa and talk," said Mark. "Now we joke that she does this only when she wants something,

Sometimes she wants to be treated like a little girl and sometimes like a young lady. The problem is figuring

out which time is which."  

    Before age 11, children like to tell their parents what's on their minds. "In fact, parents are first on the list."

said Michael Riera, author of Uncommon Sense for Parents with Teenagers. "This completely changes during

the teen years." Riera explained. "They talk to their friends first, then maybe their teachers, and their parents

last."

    Parents who know what's going on in their teenagers'lives are in the best position to help them. To break

down the wall of silence, parents should create chances to understand what their children want to say, and try

to find ways to talk and write to them. And they must give their children a mental break, for children also need

freedom, though young. Another thing parents should remember is that to be a friend, not a manager, with

their children is a better way to know them.

1. "The door to his room is always shut" suggests that the son _____.

A. is always busy with his studies   

B. doesn't want to be disturbed (打扰)   

C. keeps himself away from his parents   

D. begins to dislike his parents

2. What troubles Tina and Mark most is that _____.

A. their daughter isn't as lovely as before   

B. they can't read their daughter's mind exactly (确切地)   

C. they don't know what to say to their daughter   

D. their daughter talks with them only when she needs help

3. Which of the following best explains "the wall of silence" in the last paragraph?

A. Teenagers talk a lot with their friends.   

B. Teenagers do not want to understand their parents.   

C. Teenagers do not talk much with their parents.   

D. Teenagers talk little about their own lives.

4. What can be learned from the passage?

A. Parents are unhappy with their growing children.   

B. Parents have suitable ways to talk with their teenagers.   

C. Parents should be patient with their silent teenagers.   

D. Parents should try to understand their teenagers.

题型:计算题

货物全部灭失的赔偿请求,自货物运到期限期满后()起算。

A.10天

B.15天

C.25天

D.30天

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