With the world’s population estimated to grow from six to nine billion by 2050, researcher
Finding the resources to meet this demand in a 【S2】________, sustainable way is the cornerstone of our nation’s energy security, and will be one of the major 【S3】________ of the 21st century. Alternative forms of energy --- bio-fuels, wind and solar, to name a few --- are 【S4】________ being funded and developed, and will play a growing 【S5】________ in the world’s energy supply. But experts say that, even when 【S6】________, alternative energy sources will likely meet only about 30% of the world’s energy needs by 2050.
For example, even with 【S7】________ investments, such as the $93 million for wind energy development 【S8】________ in the American Recovery and Reinvestment Act, important alternative energy sources such as wind and bio-fuels 【S9】________ only about 1% of the market today. Energy and sustainability experts say the answer to our future energy needs will likely come from a lot of 【S10】________ --- both traditional and alternative.
A stable B solutions C significant D role E progress
F marvelous G included H growth I exactly J consist
K comprise L competitions M combined N challenges O certainly
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请帮忙给出每个问题的正确答案和分析,谢谢!