Which is incorrect about the bases in nucleic acids? a. The large bases are the purines. b. Purines always pair with pyrimidines. c. A = T and G = C. d. Hydrogen bonds form between base pairs. e. The purines are thymine and cytosine.

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.

and after water is usually warmed by the sun the water temperature raises and then evaporates .