(文)Sn=1-2+3-4+5-6+…+(-1)n+1•n,则S100+S200

题型:选择题

问题:

(文)Sn=1-2+3-4+5-6+…+(-1)n+1•n,则S100+S200+S301等于(  )

A.1

B.-1

C.51

D.52

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:选择题
已知:x=
2
-1,y=
2
,求x2+y2-xy的值.
题型:选择题

(1)某同学用多用电表测一电阻的阻值.该同学使用的是多用电表的“×10”欧姆挡,多用电表指针指到如图所示位置,则测得该电阻的阻值为______Ω.

(2)在“描绘小灯泡的伏安特性曲线”的实验中,使用的小灯泡为“6V,3W”,其它提供如下器材:

电压表V1(量程6V,内阻20kΩ)

电流表A1(量程3A,内阻0.2Ω)

电流表A2(量程0.6A,内阻1Ω)

滑动变阻器R1(0~1000Ω  0.5A)

滑动变阻器R2(0~10Ω  2A)

学生电源E(6~8V)

电键S、导线若干

①实验中要求在电压表0~6V范围内读取并记录多组不同的电压值U和对应的电流值I,以便作出小灯泡伏安特性曲线,则在上述器材中,电流表应选用______,变阻器应选用______.

②在虚线方框中画出此实验的电路图.

(3)某学习小组的同学在用打点计时器探究物体的加速度与物体的质量之间的关系实验中,不改变拉力,只改变物体的质量,得到了如下表所示的几组数据,其中第3组数据还未算出加速度,但对应该组已打出了纸带,如图所示,图中各点为选出的计数点(两相邻计数点间还有4个打点未标出)

实验次数123456
小车质量(g)2003004005006001000
小车加速度(m/s22.001.330.97~1.010.790.670.40
小车质量倒数(kg-15.003.332.502.001.671.00
①请利用下图的坐标纸建立合适的坐标系,将表中各组数据用小黑点描在坐标纸上,并将描绘的坐标点连成图线.

②分析图线得出的结论是:______.

题型:选择题

药用香树脂的是()

A.血竭

B.藤黄

C.阿魏

D.苏合香

E.加拿大油树脂

题型:选择题

信息匹配。

     下面是一篇应用文及其应用场合的信息,请阅读下列应用文和相关信息,并按照要求匹配信息。

请在答题卡上将对应题号的相应题号的相应选项字母涂黑。

A. Five Waiters and Ten Waitresses

-Aged less than 22.

-At least high school graduate.

-Good-looking; men at least 1.72 meters tall and women at least 1.60 meters tall.

-Those knowing foreign languages preferred.

-Salary 1,600-2,200 Yuan per month.

B. One Secretary

-Aged less than 30.

-Female preferred.

-Good at writing and skilled at computer. C. Accountant

-Aged between 25 and 40.

-With an experience of at least two years.

-With a degree and an accountant certificate.

-Salary 3,000-4,000 Yuan monthly.

-With a practical knowledge of computer.

D. Salesclerk

-Basic education of 12 years or more.

-Good at computer.

-Salary 1,800-2,200 Yuan monthly.

E. English Teacher

-Aged between 35 and 45.

-With a master degree and a certificate in normal university.

-With an experience abroad preferred. F. Senior Lawyer

-Aged between 45 and 50.

-With doctor degree of law.

-With an experience of senior lawyer for at least three years.

-Those knowing English preferred.

请阅读以下求职者的相关信息,然后匹配和他/她感兴趣的职位:

1. Ann has been a senior lawyer with a doctor degree in the USA for five years. She returned to China last

    week. She wants to have the same job in Beijing.

2. Lisa, a l.7-meter-tall pretty girl, has just graduated from Jingshan High School. She is good at foreign

   languages, especially English.

3. Li Wei became an English teacher in a high school in New York after he had got the master degree and a

   certificate in California University. He came back to China last week and wanted to act as an English teacher

    in Guangzhou.

4. Lanra, who is a 23-year-old lady, is good at writing as well as computer. She would like to be employed as

    a secretary.

5. Lu Bin, who can operate on the computer well, has just graduated from Guangya Middle School. She can

    have the chance to go to university, but she gives it up. She wants learn to do business as a salesgirl first.

求职者 职位

1. Ann A. Five Waiters and Ten Waitresses

2. Lisa B. One Secretary

3. Li Wei .C. Accountant

4. Laura D. Salesclerk

5. Lu Bin E. English Teacher

题型:选择题

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