<span>A. demilitarized zone.</span>
It is Tropical. Tropical climate zones are located between the tropic of cancer and the tropic of capricorn.
Answer:
1. Most common causes---- Mercury, nitrogen and phosphorus, pesticides, dissolved metals (excluding mercury) and PCBs (industrial pollutant)
2. Least common causes---- pH changes
, sedimentation and hypoxia.
Explanation:
The most common heavy metals that causes pollution are chromium (Cr), cadmium (Cd), lead (Pb), nickel (Ni), arsenic (As), mercury (Hg), zinc (Zn) and copper (Cu). Nitrogen and phosphorus application pollutes the water due to its leaching nature. The use of pesticides is very common in agriculture that cause more pollution. Pollutant comes from the industries cause water pollution and is responsible for a number of diseases.
History is 99% fact which makes it so difficult to report on it objectively.
