新GRE考试阅读逻辑题练习(第八套)_GRE阅读

新GRE考试阅读逻辑题练习(第八套)

　　Recent air-quality tests in the region around Forest Lake have revealed a slight increase in the amount of pollutants in the air.

　　Large-scale logging, which was recently begun in the forest surrounding Forest Lake, has increased the amount of decaying matter on the forest floor.

　　There is some disagreement among scientists about exactly how pollutants in the atmosphere cause acid rain.

　　Decaying matter exists on all forest floors and is an important factor in maintaining the healthy growth of the forests.

　　15. Most of Earth s surface is ocean. The ocean floor is inaccessible for extensive research without equipment of greater technological sophistication than is currently available. It must therefore be true that scientists know less about the ocean floor environment than about almost any other environment on Earth.

　　Which of the following, if true, provides the most support for the conclusion?

　　Many mountain ranges lie entirely beneath the ocean surface, yet new underwater surveying equipment has produced three-dimensional charts of them that are as accurate as those available for mountain ranges on land.

　　Strong water currents circulate on the ocean floor, but the general pattern of their movement is not so well understood as is the pattern of air currents that circulate over land.

　　In contrast to most land environments,temperature conditions at the ocean floor are generally stable and uniform, since sunlight does not penetrate far below the ocean surface.