Natural glass such as obsidian forms when ____
A)magma cools too rapidly for crystals to form
B)pegmatite melts, moves to Earth's surface and ,re-forms
C)magma cools too slowly for crystals to form
D)magma has a very low silica content
E)gas escapes through lava
A
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Which of the following is the best example of heat transfer by conduction?
A. A burner gives heat through the air without touching the object. B. A pan is placed directly on a burner. C. Seawater is drawn into a mid-ocean ridge. D. Water within the pan flows in a circular path.
The position that nature deserves to be protected in its own right is called
A. environmentalism. B. utilitarian conservation. C. global environmentalism. D. biocentric preservation.
Weathering and erosion play no role in the development of mountains.
Answer the following statement true (T) or false (F)
Which of the following terms refers to a thermometer with a small constriction just above the bulb?
A. thermocouple B. electrical thermometer C. minimum thermometer D. maximum thermometer