问题 名词解释

曲折的需求曲线模式

答案

参考答案:

是指在寡头垄断条件下,在某一价格水平上,一家企业降价,其他企业也降价,使这家企业降价后的需求曲线成为一条弹性小的需求曲线;这家企业提价,其他企业不跟着提价,使这家企业提价后的需求曲线成为一条弹性较大的需求曲线。这样,寡头垄断条件下企业的需求曲线就是一条由两部分组成的曲折的需求曲线。与此相适应,其边际收入曲线是一条中断的折线。在此模式下,如果边际成本曲线在边收入曲线中断缺口之间摆动时,企业的最优价格和最优产量决策不变;只有当边际成本曲线的变动超出边际收入曲线中断缺口的范围时,才需要对价格重新作出调整。

阅读理解

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

I live in Japan, where electronic items are a way of life, so it is no surprise that many students carry these little electronic dictionaries. E-dictionaries may be lighter and compacter (简洁的) than any paper dictionary.  小题1:  However, to me, these are pretty much the limits to their advantages.

I think e-dictionaries should be limited in their use in classrooms. 小题2:

E-dictionaries are much more expensive. In Japan, they cost as little as 10,000 yen(US$100)much as 40,000 yen, depending on how many functions you want (or think you want) and depending on how fashionable you are. My trusty Random House paper dictionary is copyrighted at1995, cost me a mere US$12.95 plus tax.

E-dictionaries are more fragile. Drop your paper dictionary. Go ahead. Hold it above your head and drop it. 小题3:

E-dictionaries need batteries. Batteries are temperature sensitive. Batteries cost money, too.

E-dictionaries have keypads. Typing in the spelling of a word is harder and more time consuming than looking through pages and using the index at the top of each page.

小题4: Sound . Little devices beep (嘟嘟声) when you press the buttons, but it is very disturbing to some people in a classroom situation or library.

Finally, let’s consider making corrections or additions. No dictionary is perfect, paper version or electronic. However, when you find something you’d like to change in the e-dictionary, you can’t do anything about it. You can pencil in some notes with the paper type. Similarly, if you learn a word that isn’t in the dictionary, a few notes of a pencil make it easy to increase its memory capacity.  小题5:And, for those students whose habit is to mark certain words with a highlight pen for ease of future reference, again, the paper dictionary wins out.

A.But it is impossible to do so with a keypad model.

B.They may even contain more words and expressions.

C. Let me add a statement about one that really troubles me.

D.Now, try this with any lightweight plastic e-dictionary, and you’ll be picking up the pieces.E.That huge, heavy paper dictionary that you see in your library looks like a building block in size and weight.

F.E-dictionaries have advantages as well as disadvantages.

G.Let’s take a look at the following reasons.

单项选择题