The measure of the total dry mass of organisms in a given area is called

this age may represent the age of the earth's accretion, of core formation, or of the material from which the earth formed. this dating is based on evidence from radiometric age-dating of meteorite material and is consistent with the radiometric ages of the oldest-known terrestrial and lunar samples.

if you listed your answers right then i believe your answer is b.

a ratio derived from the equality between two different units that can be used to convert from one unit to the other. information obtained from experiments, sometimes called experimental results. the part of the experiment that is affected by the independent variable.