A scientist identifies a rock sample as very rare. Why did he do so?
A) He observed that the rock is fine grained and has a lot of silica, making it mafic.
B) He observed that the sample is fine grained and has very little silica, making it ultra-mafic.
C) He observed that the rock is coarse grained and has a lot of silica, making it ultra-mafic.
D) He observed that the rock is fine grained and has very little silica, making it felsic.
Answer: B
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Sediments that are found on the continental slope, continental rise, and the deep-ocean floor are called ____
A) pelagic sediments B) hydrogenous sediments C) evaporites D) neritic sediments
Sleet is:
a. heavy snow. b. drizzle. c. frozen rain. d. formed with 6-sided crystals.
Compaction of soil in a garden harms plants by ________
A) decreasing aeration, decreasing infiltration, and increasing runoff B) decreasing aeration, increasing infiltration, and decreasing runoff C) increasing aeration, increasing infiltration, and decreasing runoff D) increasing the amount of clay, decreasing the amount of silt, and decreasing infiltration E) increasing aeration, decreasing infiltration, and increasing runoff
What has been the trend in human evolution since the appearance of the Cro-Magnons?
a. Several small subspecies have appeared, acclimated to mini-environments. b. Evolution has proceeded slower than usual. c. Peripheral speciation has resulted in the emergence of the Neanderthals. d. Evolution has become cultural rather than biological. e. Size of organisms has steadily decreased