Select the correct code about complex $[Cr(NO_2)(NH_3)_5][ZnCl_4]$:
$(I)$ $IUPAC$ name of compound is pentaamminenitrito$-N$-chromium$(III)$ tetrachlorozincate$(II)$
$(II)$ It shows geometrical isomerism
$(III)$ It shows linkage isomerism
$(IV)$ It shows coordination isomerism

$[Ni(CO)_4]$ is diamagnetic. Which of the following statements is correct for this complex?

The number of ions present in $2.0 \ L$ of a solution of $0.8 \ M \ K_4[Fe(CN)_6]$ is

When potassium iodide is added to an aqueous solution of potassium ferricyanide,a reversible reaction is observed in which a complex $P$ is formed. In a strong acidic medium,the equilibrium shifts completely towards $P$. Addition of zinc chloride to $P$ in a slightly acidic medium results in a sparingly soluble complex $Q$.
$(1)$ The number of moles of potassium iodide required to produce two moles of $P$ is. . .
$(2)$ The number of zinc ions present in the molecular formula of $Q$ is. . . .
Give the answer for $(1)$ and $(2)$.

Give the oxidation state,$d$-orbital occupation,and coordination number of the central metal ion in the following complexes:
$(i)$ $K_{3}[Co(C_{2}O_{4})_{3}]$
$(ii)$ $cis-[Cr(en)_{2}Cl_{2}]Cl$
$(iii)$ $(NH_{4})_{2}[CoF_{4}]$
$(iv)$ $[Mn(H_{2}O)_{6}]SO_{4}$

The correct statements from the following are:
$A$. The strength of anionic ligands can be explained by crystal field theory.
$B$. Valence bond theory does not give a quantitative interpretation of kinetic stability of coordination compounds.
$C$. The hybridization involved in the formation of $\left[Ni(CN)_4\right]^{2-}$ complex is $dsp^2$.
$D$. The number of possible isomer$(s)$ of $cis-\left[PtCl_2(en)_2\right]^{2+}$ is one.
Choose the correct answer from the options given below: