Under certain conditions, rocks of the upper mantle and lower crust melt, forming a hot liquid beneath the surface called:
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The main products of eruption are:
A. Lava
B. Gases
C. Solid materials
D. Fossils
Typical components of a volcano include:
A. Volcanic cone
B. Crater
Caldera
D. Vent
E. Magma chamber
The most common optical properties we discussed in the class include:
A. color
B. streak
C. hardness
D. fracture
E. luster
F. transparency
How many percentages do the nonsilicates make up approximately of Earth’s crust
A. 2
B. 8
C. 33
D. 76
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