Match water-cycle terms that are most closely related.

In the diagram below, the second law of thermodynamics is responsible for the processes depicted by

A) the purple squiggly lines only.
B) the black arrows only.
C) the brown arrows only.
D) the yellow squiggly lines and the black arrows.
E) the purple squiggly lines and the brown arrows.

If China needed to import just one-fifth of the grain it uses, it would take up how much of the grain exported by all the countries of the world?

A. 5% B. 15% C. 25% D. 35% E. 50%

You buy land in the tropics on steep mountain slopes covered by large trees and deep soil. You want to build a house on the land. Which of the following building plans is a very bad idea because of the danger of triggering mass wasting?

A) Sell the land because it will always be prone to mass wasting. B) Excavate a flat bench on the slope for the house, pushing the debris to the slope below and leave a cut bank above the flat bench with grass planted on the steep slope. C) Excavate the soil from the building site, install drainage systems, and backfill with gravel to prevent water accumulation. D) Terrace the slope, building on the terraces, and constructing a rock retaining well with voids to allow drainage of water.

As base level is approached by a stream, the ability of a stream to erode its bed

A) increases. B) decreases. C) remains constant.