Explain why biodiversity is important in ecosystems, what is one thing people can do to protect biodiversity?

Ido not understand. 

Answer the molar mass of magnesium is 24.305g/mol.

13 protons and 14 neutrons.  this also means that the amount of electrons also is 13 because electrons have the same amount as protons..the atomic number means the amount of protons (which effectively tells you the electrons) the atomic mass, tells you the amount of protons and neutrons in the nucleus.hope this . 

The answer is c.  na2haso4  and na2so4