A. It has mass.
Air is matter, and can't be seen thus not all matter can be seen.
Any liquid or gaseous is matter (water, air, etc.)
Since it can be liquid or gaseous it doesn't have to maintain it's shape and size to be matter.
if they are all part of the same species it would be a population
C) Eutrophication is the answer
Have a Nice Day! :)
Evolution does not occur in a straight line with one species another in a series of orderly steps with living species that are closely related share a common trait. I hope my answer has come to your help. God bless and have a nice day ahead!
When atoms in a covalent bond share electrons unequally (one atoms pulls more than the other), the bond is said to be a polar bond is formed when electrons are unequally shared between two atoms. Polar covalent bonding occurs because one atom has a stronger affinity for electrons than the other (yet not enough to pull the electrons away completely and form an ion).