17．A person has a comparative advantage at producing something if he can produce it at lower cost than anyone else．
Having a comparative advantage is not the same as being the best at something．In fact，someone can be completely unskilled at doing something，yet still have a comparative advantage at doing it!How can that happen？
Let's get some more vocabulary．Someone who is the best at doing something is said to have an absolute advantage．Lance Armstrong （自行車環(huán)法七冠王） has an absolute advantage at cycling．For all I know，Lance Armstrong may also be the fastest typist in the world，giving him an absolute advantage at typing，too．Since he's better at typing than you，can't he type more cheaply than you？That is，if someone has an absolute advantage in something，doesn't he automatically have a comparative advantage in it？The answer is no!If Lance takes time out from cycling to do all his own typing，he sacrifices the large income he earns from entertaining fans of the Tour de France （環(huán)法自由車賽）．If，instead，his secretary does the typing，the secretary gives up an alternative secretarial job-or perhaps a much lower salary as a cyclist．That is，the secretary is the lower-cost typist．The secretary，not Lance Armstrong，has the comparative advantage at typing!The trick to understanding comparative advantage is in the phrase"lower cost．"What it costs someone to produce something is the opportunity cost-the value of what is given up．Someone may have an absolute advantage at producing every single thing，but he has a comparative advantage at many fewer things，and probably only one or two things．
57．The underlined part in the second paragraph means a comparative advantageB．
    A．is equal to an absolute advantage
    B．doesn't necessarily mean the best skill at something
    C．is not completely based on an absolute advantage
    D．can fully reflect one's ability for work
58．The theory of comparative advantage can remind us of the old saying thatA．
    A．there must be a use for one's talent
    B．where there is a will，there is a way
    C．a(chǎn)ll roads lead to Rome
    D．a(chǎn)ction speaks louder than words
59．If Lance Armstrong types today for 60 dollars，but he gives it up and attends the Tour de France for 100 dollars，his opportunity cost isBdollars．
    A．40．B．60．C．100．D．160．
60．According to the author，when we cooperate with somebody，we shouldC．
    A．compare the absolute advantage
    B．consider the time of cooperation
    C．find the comparative advantage first
    D．neglect the opportunity cost．

分析 本文是有關(guān)經(jīng)濟(jì)學(xué)方面的理論，機會成本是經(jīng)濟(jì)學(xué)里的一個概念，通俗點說是你得到一個東西而失去另一個東西所付出的成本，就跟人常說"吃了碗里不可能還占了鍋里"一個道理；機會成本的準(zhǔn)確定義是指當(dāng)把一定的經(jīng)濟(jì)資源用于生產(chǎn)某種產(chǎn)品時放棄的另一些產(chǎn)品生產(chǎn)上最大的收益，或者在面臨多方案擇一決策時，被舍棄的選項中的最高價值者是本次決策的機會成本．淺顯的說，絕對優(yōu)勢是自己的某種商品跟別人的一個比較，即處于絕對優(yōu)勢或劣勢；而比較優(yōu)勢是自己多種商品之間的一個比較，選擇生產(chǎn)絕對優(yōu)勢最大的商品（或絕對劣勢最小的商品），從而實現(xiàn)利益最大化．就關(guān)系來講，比較優(yōu)勢和絕對優(yōu)勢是相關(guān)度比較高的兩個概念，而機會成本是一種付出的代價或者講失去的機會、東西．

解答 57．答案 B 推理判斷題 根據(jù)下一句In fact，someone can be completely unskilled at doing something，yet still have a comparative advantage at doing it!可知，事實上，一個人可能在某一方面不完全熟練，但是他仍然可以有比較優(yōu)勢的．故答案為B
58．答案A  推理判斷題  根據(jù)A person has a comparative advantage at producing something if he can produce it at lower cost than anyone else．Having a comparative advantage is not the same as being the best at somethin．可知，一個人只要以比別人低的成本來做事情，那么就說明他擁有比較優(yōu)勢，盡管他并不十分擅長做這件事，那么比較優(yōu)勢理論就是我們中國人所說的"天生我材必有用"，用英語說就是There must be a use for one's talent．B是"有志者，事竟成"；C是"條條大道通羅馬"D是"事實勝于雄辯"，故答案為A  
59．答案 B 推理判斷題  根據(jù)What it costs someone to produce something is the opportunity cost-the value of what is given up．可知，機會成本是指被舍棄的部分的價值，因此Lance Armstrong 放棄的是一天掙60美元，而去參加環(huán)法比賽掙100美元，他的機會成本是60美元，故答案為B
60．答案 C 推理判斷題 根據(jù)The trick to understanding comparative advantage is in the phrase"lower cost．"Someone may have an absolute advantage at producing every single thing，but he has a comparative advantage at many fewer things，and probably only one or two things．可知，我們要根據(jù)最低的機會成本來判斷得與失，機會成本越低，說明相對優(yōu)勢就大，因此與人合作時，應(yīng)該考慮相對優(yōu)勢，故答案為C

點評 本文無論是文章內(nèi)容，選取話題，還是題目的設(shè)置，對于高中的學(xué)生來說過難了些．

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