问题 解答题

某商店将进货每个10元的商品,按每个18元售出时,每天可卖60个,商店经理到市场上做一番调查后发现,若将这种商品的售价每提高1元,则日销售量就减少5个,为获得每日最大利润,则商品售价应定为每个多少元?

答案

设此商品的当日售价应定为每个x元,

则利润为:

y=(x-10)•[60-(x-18)×5]

=-5x 2+200x-1500,

=-5(x-20)2+500,

则x=20时最大利润y=5000.

答:为获得每日最大利润,则商品售价应定为每个20元.

阅读理解

根据短文内容,选择最佳答案。

What is your favorite English letter? Many of you may say QQ. Why? Because so many of you chat with your friends on QQ. What do you like about QQ? What do you talk about? The CCTV reporter, Miss Wang, interviews three kids. Let’s listen to what they say.

When do you chat on QQ? What do you talk about?

Lin Yuhan, Xi’an: On weekends. We talk about homework and chat with each other.

Tang Xuting, Shanghai: At weekends and when I don’t have much homework. We exchange test answers and chat.

Yang Yuhang, Dalian: Our class goes online together at 4-6 pm on weekends. We complain about homework, chat and talk about computer games.

What do you put on your QQ blog (博客)?

Lin: I put good articles I have found online on my blog. I also write articles myself. They are about funny things that have happened in my class.

Tang: I put pictures on my blog. Not my own photos, but pictures from my favorite Japanese cartoons (动画片) like Tennis Prince and Conan.

Yang: I put DV films on my blog. I shoot (拍摄) them during sports meetings and school parties. The most popular one is about a dancing teacher. It is so funny that everyone watches it.

How do you like QQ?

Lin: It’s a good space for us to make a record of our lives, of both good times and sad times.

Tang: My friends and I may not have time to chat at school. But we can do it on QQ. It’s very helpful to our friendships.

Yang: If you chat with friends on the telephone, your parents sometimes listen in on your conversation. There’s no such problem with QQ. You can relax and talk freely.

小题1:How many kids are interviewed about QQ?

A.Nine.

B.Six.

C.Three.

D.Two.小题2:________ comes from Shanghai.

A.Miss Wang

B.Lin Yuhan

C.Yang Yuhang

D.Tang Xuting小题3:What does Yang Yuhang talk about on QQ on weekends?

① homework    ② chat        ③ test answers ④ computer games

A.①②

B.②③

C.①②④

D.②③④小题4:What does Lin Yuhan put on her QQ blog?

A.Some pictures.

B.Good articles.

C.DV films.

D.Japanese cartoons.小题5:Which one is TRUE according to this article?

A.Lin says QQ is very helpful to their friendships.

B.Yang says he can chat freely with many friends and relax on QQ.

C.Tang says QQ is a good space for them to make a record of their lives.

D.Tang says he chats on QQ on weekdays though he has lots of homework.

单项选择题