在半径为3cm的圆中,长为2πcm的弧所对的圆心角的度数为( ) A.30° B.

题型:选择题

问题:

在半径为3cm的圆中,长为2πcm的弧所对的圆心角的度数为(   )
A.30°B.60°C.90°D.120°
考点:弧长的计算
题型:选择题


本部分为不定项选择题,每小题给出的4个选项中,至少有1项符合题意,请将正确选项全部选出。(共20题)
(一)
阅读下面材料,回答121~123题。

材料一:一对夫妻开了家烧酒店。丈夫是个老实人,为人真诚、热情,烧制的酒也好,人称“小茅台”。有道是“酒香不怕巷子深”,一传十,十传百,酒店生意兴隆,常常供不应求。为了扩大生产规模,丈夫决定外出购买设备。临行前,他把酒店的事都交给了妻子。几天后,丈夫归来,妻子说:“我知道了做生意的秘诀。这几天我赚的钱比过去一个月挣的还多。秘诀就是,我在酒里兑了水。”丈夫给了妻子一记重重的耳光,他知道妻子这种坑害顾客的行为,将他们苦心经营的酒店的牌子砸了。“酒里兑水”的事情被顾客发现后,酒店的生意口渐冷清,最后不得不关门停业了。
材料二:1835年,摩根先生成为一家名叫“伊特纳火灾”的小保险公司的股东。不久后,一家在伊特纳火灾保险公司投保的客户发生了火灾。按照规定,如果完全付清赔偿金,保险公司就要破产,股东们纷纷要求退股。摩根先生斟酌再三,认为信誉比金钱更加重要。他卖掉住房并四处筹款,收购了所有要求退股的股份,并将赔偿金如数付给了投保的客户。从此,伊特纳公司声名四起,成为人们心目中最讲信誉的保险公司,客户蜂拥而至。

材料二中,摩根成就事业的重要原因是( )。

A.一次偶然的机遇

B.收购了所有要求退股的股份

C.认为信誉比金钱更加重要

D.敢于冒险的精神

题型:选择题

阅读理解。

     Most people want to be happy, but few know how to find happiness. Money and success alone do not

bring lasting happiness. Aristotle, a Greek thinker, said, "Happiness depends upon ourselves." In other words,

we make our own happiness. Here are a few suggestions to help you be happier.

     The first secret of happiness is to enjoy the simple things in life. Too often, we spend too much time

thinking about the future-for example, getting into college or getting a good job-that we fail to enjoy the

present. You should enjoy life's simple pleasures, such as reading a good book, listening to your favorite

music, or spending time with close friends. People who have several close friends often live happier and

healthier lives.

     Another secret to living a happy life is to be active. Many people go dancing or play sports. People can

forget about their problems and only think about the activities.

     Finally, many people find happiness in helping others. Studies show that people feel good when they

spend their time helping others. If you want to feel happier, do good things for someone. You can help a

friend with his or her studies, go shopping to buy food for an elderly person, or simply help out around the

house by washing the dishes.

1. The best title (标题) of this passage is ________.

A. The Secrets of  Happiness

B. Money Makes You Happy

C. Ideas for Helping Other People to Be Happy

D. Good Friends Make You Happy

2. The second paragraph tells us that ________.

A. the more friends you have, the happier you'll be

B. we shouldn't think about our future

C. happiness is to enjoy the simple things in life

D. some people fail to live a happy life

3. The passage gives us ________ pieces of advice on happiness.

A. one

B. two

C. three

D. four

4. The writer thinks that ________.

A. everyone knows how to live a happier life

B. It's wrong to spend time on work

C. hobbies take up too much time

D. doing good things for someone can make you happier

5. Which of the following is not mentioned in the passage?

A. Reading a good book

B. Traveling to a foreign country

C. Playing a sport

D. Spending time with close friends

题型:选择题

关于β受体激动剂,错误的是()

A.地匹福林属于β受体激动剂

B.兴奋β1受体

C.既降低小梁网房水流出阻力,又增加葡萄膜-巩膜途径房水引流

D.禁用于闭角型青光眼

E.血管收缩和散瞳均为其主要不良反应

题型:选择题

分馏必备的条件有哪些?

题型:选择题

穿戴防护用品顺序

更多题库