阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。

When scholars of international relations predict that the 21st century will be a “Chinese century”, they are full of reasons. 【小题1】 America remains the only superpower, China is responsible for an important share of global change. Since 【小题2】 start of the financial crisis in 2008, for example, China has accounted 【小题3】45% of the gain in world GDP. In 1990 about 750 million Chinese people lived in extreme poverty; today fewer than 10 million do. Its GDP per person, in terms of purchasing-power, 【小题4】 (rise) ten times since 1990.

China’s amazing 【小题5】 (perform) has greatly affected the world’s economic output. The Economist has worked out a geographic center of the global economy by 【小题6】 (take) an average of each country’s latitude and longitude(经纬度), 【小题7】 (measure) by its GDP. At the height of America’s control, this point 【小题8】 (previous) sat in the north Atlantic. But China has pulled it so far east 【小题9】 the global center of economic gravity 【小题10】 (be) now in Siberia.