What’s the greenhouse effect? A. The release of extra moisture from water vapor
B. The trapping of warm air in cities
C. Human-caused global warming
D. The regulation of atmospheric and surface temperatures

Gold is not now being extracted from seawater. why not? a. it would be too disruptive to marine life to develop any marine mineral resources b. there is no gold in seawater c. we don't know how to extract minerals from seawater d. it would be too costly and difficult to separate the small amount of gold from the very large amounts of halite and other minerals

Select the correct text in the passage. the moving continents affect all subsystems on earth. which sentence identifies a potentially negative consequence of shifting continents? the supercontinent pangaea began to break up about 175 million years ago. [during this process, more coastline was exposed as the landmasses separated]. [the rearrangement and displacement of these huge landmasses resulted in the diversity of plants and animals we see on earth today]. [the movement of the plates sometimes leads to earthquakes and tsunamis]. however, over the long course of earth's history, their effects are usually minimal. in oceans, the plate movements usually lead to seafloor spreading. [seafloor spreading often results in the formation of underwater ranges of mountains].

This word for a bug or malfunction was popularized in the 1962 book into orbit by the mercury astronauts