The Clean Air Act Amendments established rules on a variety of pollutants. Since 1990, by what approximate amount have ambient sulfate concentrations decreased in most regions of the U.S.?
W) 10%
X) 25%
Y) 50%
Z) 90%
✔️Answer:Y) 50%
🚀
Take Your Prep to the Next Level
Practice with interactive modes, adaptive testing, and detailed stats on our main app.