Which population serves the function of autotrophs in a lake community?

Compare the valence electron configuration of the nobles gas elements seen here. what statement is correct?

What is the temperature of one mole of helium gas at stp?

This chart lists four kinds of polymers and their sources. what can be known about all four polymers, despite their differences? they come from living things. they share ionic carbon bonds. they are at least 100 monomers long. they are made of repeating subunits.