Give two regions of the body where the bones act as a protection for vital organs. name the bones and the organs they protect.

The skull protects the brain,  ribs form a cage that shelters the heart and lungs

Explanation:

The skull protects the brain; the thorax (sternum, ribs and spine) protects the heart, lungs and other viscera (organs within the thorax). The ribs form a cage that shelters the heart and lungs, and the pelvis helps protect the bladder, part of the intestines, and in women, the reproductive organs. Bones are made up of a framework of a protein called collagen, with a mineral called calcium phosphate that makes the framework hard and strong.

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.