Answer:
It has gotten worse.
Explanation:
In the past 30 years, air quality in the United States has declined almost exponentially. Pollution is the main reason for the declination of air quality in the United States, but there are different kinds of pollution, including light pollution, noise pollution, air pollution, water pollution, etc. Air pollution can be caused by primary or secondary pollutants. Primary pollutants include carbon, nitrogen, and sulfur oxides as well as just general particles in the air. Secondary pollutants are formed when pollutants are exposed to sunlight via chemical reactions.
Yes because igneous rocks are made from lava that cools in or outside of a volcano and sedimentary rocks are simply made of sand rocks and other things that just stick together in layers and forms a rock. I don't know if I'm being clear though... Sorry I speak French but I hope I helped :)
The correct answer in this question is letter B. The male reproductive parts of a flower are called stamens. It is composed of an anther and a filament. The pollen, which is located in the anther, contains the male reproductive cells.
An earthquake is the perceptible shaking of the surface of the Earth, resulting from the sudden release of energy in the Earth's crust that creates seismic waves.
Organisms compete for the resources they need to survive- air, water, food, and space. In areas where these are sufficient, organisms live in comfortable co-existence, and in areas where resources are abundant, the ecosystem boasts high species richness.