Part 3
15.C
16-20 D A D B C

15.這一段主要講在具體的市場之外發(fā)展出了一個抽象的市場，用來交易想法和知識。只有通過工作機會才能對知識進行交易。而只有工人提供自己的知識，才有可能進行交易，否則，別無他法。而工作量又是僅僅通過時間衡量的。通過這一句可以看出，因該選擇C Opportunities to exploit your knowledge were limited in the past.其他選項在文中都沒有提及。
16. But today the internet is making the distribution of knowledge ever easier. This is reducing the friction in the knowledge economy.從這兩句可以看出應該選擇D the internet facilitates the development of the knowledge economy.
17.Now you can sell your knowledge to newer, younger computer dealers who have no way to build up this knowledge without losing thousands of pounds finding it out the hard way. 從這一句可以看出選擇A。
18.It’s a renewable resource. Better yet, its worth actually increases.從這句可以看出選擇D Its value accumulates.
19.The value of knowledge often depends on variables such as time and the credibility of the seller.通過這一段可以看出選擇B

introducing compatible parties.
20.通過最后一段可以看出選擇C。