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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Fill in the blank(s) with the appropriate word(s).
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Fill in the blank(s) with correct word
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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
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Strip mining can be environmentally benign
What will be an ideal response?
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