1. Marine snow refers to A Appearance of the water during freezing weather.
B. animal and plant plankton that die and drift downward.
C. white sand beaches that form on ocean coasts.
D. algai blooms that form on the surface of a body of water.
E. weather over the Arctic that contributes to the ce pack

B. animal and plant plankton that die and drift downward.

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.