Which of the following materials is most readily dissolved by water?
A. Clay minerals
B. Silica
C. Quart
D. Calcite
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What percentage of the groundwater in the total volume of all liquid freshwater?
A. 94%
B. 3.6%
C. 2%
D. 0.05%
What percentage of the groundwater in the total volume of freshwater?
A. 84.9%
B. 14.6%
C. 0.55%
D. 0.004%
Why are particles of similar size usually found together deposited by streams?
A. Particles of smaller size usually get deposited in the faster-moving parts of the stream, but the larger particles can be deposited in the slower parts.
B. Particles drop in order according to weight and settling velocity as a stream’s velocity drops, starting with the largest and ending with the smallest.
C. Particles drop in order according to size and shape as a stream’s velocity increases, starting with the smallest and ending with the largest.
D. Particles of larger size usually get deposited in the slower-moving parts of the stream, but the smaller particles can be deposited in faster-moving water.
Since Earth's water cycle is balanced, the average annual precipitation worldwide must equal the quantity of water infiltrated.
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