The World Trade Organization was founded in 1995. It absorbed the General Agreement on Tariffs and Trade (GATT), which covers trade in manufactured and agricultural goods. The WTO also regulates trade in services and in intellectual property, which includes such creations (作品)as books, computer softwares, and recordings.

The WTO is one of three major organizations that oversee (监督)international economic relations among governments. The other two are the International Monetary Fund (国际货币基金会), which works to improve payment arrangements and other financial dealings between countries, and the World Bank, which provides loans to poorer nations for economic development. WTO headquarters are in Geneva, Switzerland.

1) The World Trade Organization was founded in (46) .

2) The GATT covers trade in (47) goods.

3) The WTO is one of three major organizations. The other two are the (48) and (49) .

4) WTO headquarters are in (50) , Switzerland.

50（）

设f(x)在(-∞，+∞)上有定义，且对任意的x，y∈(-∞，+∞)有|f(x)-f(y)|≤|x-y|．证明。