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PolarNik [594]
3 years ago
5

Why was 1990 an important year regarding air quality?

Chemistry
2 answers:
DerKrebs [107]3 years ago
4 0

Answer:

100%

2 and 4

Explanation:

Valentin [98]3 years ago
3 0

Why was 1990 an important year regarding air quality? Check all that apply.

2.Cost-effective ways to reduce pollution were emphasized.


4.Modifications and improvements were made to the Clean Air Act.


i just took the test this is 100% correct

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