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Predicted concentrations of NO based on proximity to a freeway (FWY) or non-freeway (NFWY) major road. Vertical bars indicate the upper bound of the 95% confidence limit for each prediction. Results are shown for two types of communities: (a) within the LA basin with overall mean NO level 26.0 p.p.b. and (b) outside the LA basin with overall mean 7.9 p.p.b.
