Over the past 20 years, the major pollutants in our world have
a. decreased significantly
b. increased significantly
c. stayed at the same levels
d. decreased slightly

It might seem like pollution is decreasing, but this is only (if at all) the case in the developed countries. In fact, in the developing countries, as well, as as a global trend, poluttion is still increasing the world- answer b.

Answer (6) six inches of the floor;