1. Summarize the story of air pollution in Los Angeles and how it represents the larger problem of air pollution around the world. 2. What is the key concept for this section? Summarize the U.S. air...

1. Summarize the story of air pollution in Los Angeles and how it represents the larger problem of air pollution around the world.

2. What is the key concept for this section? Summarize the U.S. air pollution laws and how they have worked to reduce pollution. Explain how these laws can be strengthened, according to some scientists.