Q.1
The bacteria that make methane
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are mostly found in the atmosphere.
live mainly in the ocean.
live in anaerobic (oxygen-free) conditions.
did not evolve until 50 million years ago.
Q.2
As methane rises through the ocean water, it can
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dissolve to form sodium bicarbonate.
freeze and settle to the bottom.
form the cage-like structure methane hydrate.
be oxidized into carbon dioxide.
Q.3
When the concentration of carbon dioxide in the atmosphere rises, plants tend to
*
grow slower.
grow faster.
die.
grow as usual, without any obvious effect.
Q.4
Methane hydrates in the Arctic
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store huge amounts of energy.
can be used as a source of natural gas.
exist only in a certain range of pressure and temperature.
all of the above.
Q.5
One reason to doubt that methane releases will cause global warming feedback comes from
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ice cores, which show that methane levels rose following warmings in the past.
low levels of methane in the atmosphere near the North Pole.
studies showing that methane is much weaker than carbon dioxide as a greenhouse gas.
the inability to find methane in the atmosphere above the ocean.