I attached the pic. NH2 is amine group, COOH is carboxyl group.
Coralline and calcareous algae build-ups are very essential for the development of coral reefs. In addition, when these coralline and calcareous algae tends to "stick" on landforms below the ocean surface, and as these life forms grows and continuously expands, they now form what we call "reefs."
C. the answer is c. i just took this test on keystone (i think this is keystone question. right?0
A hydrometer is an instrument that measures the specific gravity (relative density) of liquids. The ratio of the density of the liquid to the density of water. A hydrometer is usually made of glass, and consists of a cylindrical stem and a bulb weighted with mercury or lead shot to make it float