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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Environmental ethics is best defined as ________
A) studying the moral relationships of humans to the environment and the environment's living organisms B) studying the rightness and wrongness of human actions C) actions taken by humans in the environment in which they live that have impact D) studying the economic value of all living things in their environment E) the extrinsic value placed on people, organisms, and objects in the environment
Waves of translation form breakers along a shoreline
Indicate whether the statement is true or false
A(n) ____________ is a ring-shaped island built of calcium carbonate enclosing, or almost enclosing, a shallow
lagoon from which no land protrudes. Fill in the blank(s) with the appropriate word(s).
?A low, lumpy cloud layer that appears in rows, patches, or rounded masses would be classified as
a. ?nimbostratus. b. ?stratus. c. ?altocumulus. d. ?stratocumulus. e. ?cirrostratus.