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A. use
B. inform
C. ask
D. teach
What is the beneficial point of some microbes consuming plant-produced methane？
A. Methane becomes less poisonous
B. Methane is turned into a fertilizer
C. Less methane reaches the atmosphere
D. Air becomes cleaner
？？What do experts say about the earth's fuel reserves？？？
A. The earth's fuel reserves will be accessible for the next 50 years
B. There'will soon be an energy crisis
Conventional reserves will soon become inaccessible
D. Fuel demand will decline
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A. how
B. why
C. where
D. what
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