How long did it take before free oxygen could build up in the atmosphere?
A. 2 billion years
B. 20 million years
C. 200 million years
Answer: A
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The harvest of organisms is more likely to be sustainable if organisms are captured
A) before they have had a chance to reproduce. B) while they are still in the egg or seed stages. C) after they have had a chance to reproduce. D) during the first year of their life.
Some observers of the Middle East believe political tension over this resource could escalate to war in the next few years
A) brine B) cobalt C) high-grade coal deposits D) rare earth metals E) water
What is the ratio of parent atoms to daughter atoms after three half-lives?
What will be an ideal response?
What is the difference between a fracture zone and transform fault?
a) A transform fault is perpendicular to the mid-ocean ridge, but a fracture zone is not b) A transform fault is a crack in the crust, but a fracture zone is a hole in the crust that extends into the mantle c) A transform fault runs along a zone of weakness in the crust while a fracture zone runs along a zone of strong, erosion-resistant rock d) Transform faults run between offsets in a mid-ocean ridge while fracture zones extend beyond the offsets e) Transform faults are stationary while fracture zones have strike-slip motion