Education expert Eric Hanushek estimates that the difference between a great teacher and bad teacher in a child's lifetime earnings is hundreds of thousands of dollars.

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Professor Alex Kemp, a petroleum economics expert at the University of Aberdeen, described the Falklands oil reserve estimates as "optimistic, " adding that even if they are proven, the cost of exploiting them could still be prohibitive.

CNN: STORY HIGHLIGHTS

Research by Panos Ipeirotis, a computer expert at the Stern School of Business at New York University, estimates that Mechanical Turk alone engages 500, 000 active workers in more than 100 countries, with workers heavily concentrated in two countries: the United States (with 50 percent of the total) and India (with 40 percent).

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Sarah Johnson, a small dams expert for Trout Unlimited, estimates that 25 percent of all dams in the United States are outdated.

CNN: Study opens floodgates on dam removal

Yet he estimates there are only about 30 scholars in China who are truly expert in the language.

ECONOMIST: One hundred years on, only a few native speakers remain