A bright red nebula is called an HII region when it contains
A. molecular hydrogen gas, H2.
B. hydrogen atoms which have been ionized by ultraviolet radiation.
C. hydrogen which is generating 21-cm radio waves.
D. hot hydrogen gas thermally glowing.
Answer: B
Physics & Space Science
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Strengthening by cooling a solid solution and forming small particles of a new phase is called _________hardening
Fill in the blank(s) with the appropriate word(s).
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The ________ on the edges of the continents come from subduction of oceanic basalt beneath the advancing continental plate
Fill in the blank(s) with correct word
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Strip mining can be environmentally benign
What will be an ideal response?
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Determine the energy stored in the 60-?F capacitor
a.
2.4 mJ
b.
3.0 mJ
c.
3.6 mJ
d.
4.3 mJ
e.
6.0 mJ
Physics & Space Science