21. what is biodiversity? 22. describe the water in an estuary. 23. what bodies of water have the highest biodiversity? 24. where does an organism live if it is a terrestrial organism? 25. make a flow chart of the water cycle beginning with the sun providing energy for heat. 26. where does most of our drinking water come from? 27. why do we monitor our water supply? 28. what man made problems would cause water levels to decrease in a city? 29. what is the dominant physical feature of planet earth? 30. what is the water table?

what subject is this

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.