Which occurrence most likely led to the other
three?
(1) human population growth reached 6.8 billion
in 2010 and it continues to increase.
(2) the number of african elephants has
declined from 1.2 million in 1979 to about
20,000 today.
(3) approximately 6,500 gallons of oil were
spilled into a river in illinois after a pipeline
broke.
(4) at one time, rain forests covered 14 percent
of earth and today they cover only 6 percent.