Choose all the answers that apply.

the sun

is the only star in our solar system
is the largest star in the milky way galaxy
is made mostly of hydrogen and helium
will continue to release light and heat forever
has a solid core made of iron and nickel

C is the correct answer. > is made mostly of hydrogen and helium

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.