What is the oxidation state of chlorine atom in hypochlorous acid?

The oxidation number of $P$ in $Mg_3(PO_4)_2$ is ........

What is the oxidation number of sulphur in $SO_3$?

What are the oxidation states of phosphorus in the following:
$(i)$ $H_{3}PO_{3}$
$(ii)$ $PCl_{3}$
$(iii)$ $Ca_{3}P_{2}$
$(iv)$ $Na_{3}PO_{4}$
$(v)$ $POF_{3}$

What is the oxidation number of $P$ in $KH_2PO_2$?

The oxidation state of nitrogen is incorrectly given for:
Compound $\to$ Oxidation state