Chemical methods--It includes ion exchange, precipitation, oxidation and reduction, and neutralization.........
Thermal methods--In this, high-temperature incineration, which not only can detoxify certain organic wastes but also can destroy them....
Biological treatment-- It is of certain organic wastes, such as those from the petroleum industry by a special method called landfarming
Physical treatment-- It concentrates, solidifies, or reduces the volume of the waste. Physical processes include evaporation, sedimentation, flotation, and filtration....
Nitrogen,Phosphorus and Potassium
The answer is D. In a
geological era, when the plants and animals
in the then environment die, they get buried
in sediments. These sediments are covered
by other sediments of another geological
time within which are the remains of dead species
of the then geological era. These sediments from different geological times have different properties hence
form visible strata that can be studied to identify the kind of environment in the then geological time. Their
fossils can also be studied to identify
the kind of species that roamed the earth during the time.
