已知等差数列{an}中,a1=1,a3=-3. (I)求数列{an}的通项公式;

题型:解答题

问题:

已知等差数列{an}中,a1=1,a3=-3.

(I)求数列{an}的通项公式;

(II)若数列{an}的前k项和Sk=-35,求k的值.

考点:等差数列的通项公式等差数列的前n项和
题型:解答题

2006年7月,美国福布斯网站公布了全球十大富豪每分钟的净收入榜单。比尔·盖茨以每分钟6 659美元的收入排在榜首。一些人羡慕盖茨,崇拜货币,是因为(  )

A.货币是商品交换发展的产物

B.货币是由金银来充当的

C.货币是人们的劳动产品

D.货币可以与一切商品相交换

题型:解答题

阅读理解。

     Back in the fifteenth century, in a tiny village near Nuremberg, lived a family with eighteen children. In

spite of the hopeless condition, two of the children, Albrecht Durer and Albert, had a dream. They both

wanted to pursue their talent for art.After many long discussions, the two boys finally worked out an agreement.They would toss a coin.The loser would go down into the nearby mines and, with his earnings,

support his brother who attended the academy.Then, when that brother who won the toss completed his

studies, in four years, he would support the other brother at the academy.

     Tossing a coin, Albrecht Durer won and went off to Nuremberg.Albert went down into the dangerous mines and, for the next four years, supported his brother, whose work at the academy was almost an

immediate sensation (轰动). By the time he graduated, he had earned considerable fees for his outstanding works.

     When the young artist returned to his village, the Durer family held a festive dinner to celebrate

Albrecht's triumphant (胜利的)homecoming.Albrecht drank a toast to his beloved brother for the years

of sacrifice that had enabled him to complete his dream."And now, Albert, blessed brother of mine, now

it is your turn. Now you can go to Nuremberg to look for your dream, and I will take care of you."

     Tears streaming down his pale face, Albert sobbed, "No...no...It is too late for me.Look...look at

what four years in the mines have done to my hands!The bones in every finger have been broken at least

once, and lately I have been suffering from arthritis(关节炎)so badly in my right hand that I cannot even

hold a glass to return your toast, much less draw delicate lines with a pen or a brush."

     To show thanks to Albert for all that he had sacrificed, Albrecht Durer painstakingly drew his

brother's injured hands with palms together and thin fingers stretched skyward.He called his powerful

drawing simply "Hands", but the entire world almost immediately opened their hearts to his great

masterpiece and renamed it "The Praying Hands".The next time you see a copy of that touching creation,

let it be your reminder-no one ever makes any success alone!

1.Why did the two brothers work out the agreement?

A. They were so curious as to make a joke.

B. Their family couldn't afford the academy.

C. One of the brothers was supposed to go into mines.

D. They wanted to support the other sisters and brothers.

2.The underlined word "whose" in Para.2 refers to     __ .

A. the Durer family's  

B. the miners?  

C. Albert's    

D. Albrecht's

3. Which of the following statements is NOT true about Albrecht Durer?

A. He began to earn his living after graduation.

B. He did perfectly well at the academy.

C. He wanted his brother to go to the academy.

D. He created great masterpieces.

4.Which of the following is the correct order of the story?

a. Albrecht went to Nuremberg.

b. Albert supported his brother.

c. The Durer family held a festive dinner.

d. Albrecht drew his brother's injured hands.

e. The brothers tossed a coin.

A. b, a, c, d, e    

B. a, e, c, d, b    

C. e, a, c, b, d    

D. e, a, b, c,

5. What can we learn from the story?

A. One can achieve success simply on his own.

B. Any success requires the help of others.

C. It's other people who contribute to one's success.

D. Nobody could succeed without good guidance.

题型:解答题

下列化学用语正确的是[ ]

A.硫的原子结构示意图:

B.顺-2-丁烯的结构简式:

C.乙酸的实验式:C2H4O2

D.原子核内有8个中子的氧原子:188O

题型:解答题

实验室常用乳糖操纵子控制目的基因的表达,别乳糖作为诱导剂使用,它在乳糖操纵子启动表达中的作用是(  )

A.作为辅阻遏物结合于阻遏物与RNA聚合酶之间

B.作为阻遏物结合于乳糖操纵子的操纵序列上

C.使阻遏物变构而失去结合特异性DNA序列的能力

D.是乳糖操纵子结构基因的表达产物

E.是乳糖操纵子转录的产物

题型:解答题

进程是操作系统中的一个重要概念。进程是一个具有一定独立功能的程序在某个数据集合上的一次 (5) 。进程是一个 (6) 的概念,而程序是一个 (7) 的概念。进程的最基本状态有 (8) 。在一个单处理机中,若有6个用户进程,在非管态的某一时刻,处于就绪状态的用户进程最多有 (9) 个。

A.物理

B.逻辑

C.动态

D.静态

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