Which among the following compounds exhibits $+2$ oxidation state of oxygen?

Fill in the blanks:
$(1)$ Oxidation number of $Cr$ in $Na_3Cr_3O_{10}$ is ........
$(2)$ Oxidation number of $H$ in lithium aluminum hydride $(LiAlH_4)$ is .......
$(3)$ Oxidation number of oxygen in potassium ozonide $(KO_3)$ is .........
$(4)$ Oxidation number of $C$ in fullerene and graphite is .......

Arrange the following molecules in the increasing order of the oxidation number of $S$: $SO_3^{2-}$,$S_2O_4^{2-}$,and $S_2O_6^{2-}$.

The oxidation state of sulfur in the anions $SO_3^{2-}$,$S_2O_4^{2-}$,and $S_2O_6^{2-}$ increases in the order:

Which of the following statements is correct regarding $H_2S_4O_6$?

Calculate the oxidation number of $Fe$ in $Fe_{0.94}O$.