>>reporter: the zhou (pronounced joe) family tend a soccer field sized plot some 90 km from china's border with myanmar. they switched from growing sugar cane to coffee seven years ago, and in doing so, doubled their income. at today's commodity price, this household of four makes around two and a half thousand us dollars annually. >>erluan: it doesn't take a lot of work, even the children and oldfolk here do it. and the income, well, it's quite nice. >>reporter: of course, the word nice is relative. but for the 40,000 coffee growing families across yunnan, one of china's poorest provinces, only tending tobacco pays as well. it for export. but its output hardly registers on the world stage. the total coffee growing area covers just 280 sq km, or around one sixtieth the size of beijing. >>reporter: brazil is the world's biggest coffee producer with over 39 million bags in 2009, more than double the combined harvest of latin america's other big players.>>in africa, the beverage's birthplace, ethiopia and uganda lead the continent.while india and indonesia are serious asia producers.vietnam,

. >> rose: back to mao tse-tung and zhou enlai. how were they different? how did they work together? how was... >> well, mao destroyed chao enlie. >> rose: i kw. >> at the end mao destroyed almost everybody. >> numrwo man to mao. and mao survived. i know a leader in another country once who was number two and he said his trick... the trick s to be close enough so that no one else could come between but not so close that the number onefeltthreatened. this man didn't... >> rose: so he lost out, too? >> he lost out, too. but mao was a propheti type. he had his own visions of a unique chise ethical mission and he was assailed by his mortality so that he didn't feel he could start this and let somebody else complete it. he had to try to complete in the his lifetime. so he... most revolutionarys that you can study in history have a specific goal and when they reach it they then institutionalize that goal. mao didn't want to institutionalize anything. he wanted permanent revolution. he wanted peoe to go through this process. >> rose: but he wanted permanent revol