The research on coins stored from 100 B.C. to 50 C.E. indicates that ______.
A. civil wars reduced about 1000 000 people
B. the Augustan censuses included women and children
C. population explosion hypothesis is reasonable
D. some civil wars didn't cause high casualties
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A.They would be killed by the human immune system.B.They would die once brought to the
A. They would be killed by the human immune system.
B. They would die once brought to the surface.
C. Many precautions and remedies are available.
Drilling operations are always closely monitored.
A.Fort Dearborn was built in 1833 in the place that would become Chicago.B.Chicago did
A. Fort Dearborn was built in 1833 in the place that would become Chicago.
B. Chicago didn't officially become a town in 1893.
C. Only 350 people lived in Chicago when it officially became a town.
D. Another 350 people moved into Chicago when it became a town.
A.It is inconvenient to take the baggage onto it.B.It is difficult to spare the room f
A. It is inconvenient to take the baggage onto it.
B. It is difficult to spare the room for wheelchairs.
C. It is dangerous to get in from both sides of it.
D. It is easy to have an accident on a movable platform.
M: Well, yes, it's very exciting. For a long time we'd suspected the presence of such organisms, but we lacked substantial evidence.
W: How did you confirm the existence of the bacteria?
M: Well, technology helped. Our drilling techniques have improved significantly, and so the risk that Surface bacteria could be mistaken for those found at much greater depth was reduced. With the new techniques, we could get much deeper into the Earth.
W: How far down did you actually get?
M: In one case, about three kilometers. We were surprised, I must tell you, that there were organisms that far down.
W: You know, it sounds like fiction, something like a lost world.
M: Let's call it a hidden biosphere, and it's probably a very extensive one. The mass of the living organisms below the surface may be equal in size to the mass of the surface bacteria.
W: Have you found any unique life-forms?
M: Yes. We've found a very special organism. Let's call it Type-A bacterium. It can live and grow only where there is no oxygen.
W: Is there any danger of these bacteria infecting people when you bring them to the surface?
M: These bacteria were adapted to an environment that's completely different from humans'. That's to say. they could not survive in our environment. So we really don't need to worry about these bacteria causing illness in people.
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A. Organisms far below the Earth's surface.
B. New drilling methods.
C. A hidden underground world.
D. Rare and infectious bacteria.