What is the oxidation number of $Ru$ in $[Ru(NH_{3})_{5}H_{2}O]Cl_{2}$?

The compound $K_3[Fe(CN)_6]$ is named as:
$(1)$ Potassium hexacyanoferrate $(II)$
$(2)$ Potassium hexacyanoferrate $(III)$
$(3)$ Potassium ferricyanide
$(4)$ Hexacyanoferrate $(III)$ potassium

The $IUPAC$ name of $Fe(CO)_5$ is.......

The oxidation state of $Fe$ in $Na_3[Fe(NH_3)(CN)_5] \cdot 2H_2O$ is ..............

State the $IUPAC$ name of the following complex: Sodium nitroprusside.

The $IUPAC$ name of $K_2[Zn(OH)_4]$ is ............ .