18. Which of the following is a major cause of air pollution? a. dumping waste in landfills
b. using wind and solar energy
C. releasing waste into rivers, lakes, streams
d. burning fossil fuel

Which occurs when air is compressed? air molecules move slower. air temperature rises and air molecules move faster. air temperature decreases. air temperature decreases and air molecules move faster.

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].

If scientists only detect p waves in a certain layer of earths interior what does that tell us?