Much of Earth's water supply originated from
A) asteroids.
B) icy comets.
C) gases expelled from the Sun; i.e., solar wind.
D) photosynthesis.
B
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Which of the following is not a characteristic of an actively erupting volcano?
A) Totally covered in a fresh blanket of clean, white snow B) Billowing ash column rising into the sky C) Glowing lava flows moving down mountain slopes D) Rapidly melting glaciers/snowpack producing massive mudflows
Which of the following is NOT a part of the nuclear fuel cycle?
A. fabricating fuel into fuel rods B. enriching the uranium ore C. mining uranium ore D. gas cooling of the reactor
When cultivars require adaptations not currently in their genetics, plant breeders
A) may treat the seeds with chemicals that cause mutations in order to try to generate new forms. B) often introduce traits found in wild varieties of the plant. C) may try to introduce genetic traits found in pests of the crops. D) use fertilizers to change the chemistry of the crops.
Which of the following uses the largest percentage of the Earth's groundwater?
A) Mining B) Hydroelectric power C) Irrigation D) Public consumption