The lunar mare are radioactively dated at:
A) 4.6 billion years old, forming first among the lunar features.
B) 4.2-3.9 billion years old, comparable to the adjacent highlands.
C) 3.9-3.2 billion years old, forming after most of the bombardment was over.
D) 3.5-2.5 billion years old, similar to the formation of our own oceans.
E) less than a billion years old, the most recent additions to the Moon.
C
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Double-lobed radio galaxies are an effect of black hole jets
a. True b. False Indicate whether the statement is true or false
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A. 13.8 N B. 90.9 N C. 138 N D. 909 N
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A) conduction. B) convection. C) radiation. D) all of the above