At about what frequency is Earth struck by a meteorite large enough (about 10 km in diameter) to cause mass extinctions?
A. about every 100 million years
B. about every 10 million years
C. about every 1 million years
D. This has yet to occur on Earth.
Answer: A
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lagoon from which no land protrudes. Fill in the blank(s) with the appropriate word(s).
Environmental ethics is best defined as ________
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a. ?nimbostratus. b. ?stratus. c. ?altocumulus. d. ?stratocumulus. e. ?cirrostratus.
Waves of translation form breakers along a shoreline
Indicate whether the statement is true or false