50. One approach to resolving air pollution problems, intended to reduce a particular pollutant over an entire industrial
region by treating all emission sources as if they were under one bubble is called
a. emissions trading.
b. blanket controls.
c. comprehensive emissions regulation.
d. the clean air provision.
51. The purpose of Superfund legislation was to
a. identify toxic waste sites.
b. eliminate dumping of toxic wastes.
c. clean up hazardous waste dumps and spills.
d. prevent land degradation.
52. In the Montreal Protocol of 1987, most of the nations that produced or used CFCs agreed to
a. a gradual phase-out of those materials.
b. limit future use of CFCs to amounts produced in that year.
c. an immediate ban on all CFCs.
d. a quick phase-out of CFCs.