Assign oxidation states to all of the following atoms.

a. \(\mathrm{UO}_{2}{ }^{2+}\)

b. \(\mathrm{As}_{2} \mathrm{O}_{3}\)

c. \(\mathrm{NaBiO}_{3}\)

d. \(\mathrm{As}_{4}\)

e. \(\mathrm{HAsO}_{2}\)

f. \(\mathrm{Mg}_{2} \mathrm{P}_{2} \mathrm{O}_{7}\)

g. \(\mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}\)

h. \(\mathrm{Hg}_{2} \mathrm{Cl}_{2}\)

i. \(\mathrm{Ca}\left(\mathrm{NO}_{3}ight)_{2}\)