Excess of $aq. NH_3$ can dissolve

The number of species having a square planar shape from the following is $........$.
$XeF_4$,$SF_4$,$SiF_4$,$BF_4^{-}$,$BrF_4^{-}$,$[Cu(NH_3)_4]^{2+}$,$[FeCl_4]^{2-}$,$[PtCl_4]^{2-}$

Among the statements $(a)-(d)$,the incorrect ones are:
$(a)$ Octahedral $Co(III)$ complexes with strong field ligands have very high magnetic moments.
$(b)$ When $\Delta_{0} < P$,the $d-$electron configuration of $Co(III)$ in an octahedral complex is $t_{2g}^{4} e_{g}^{2}$.
$(c)$ Wavelength of light absorbed by $[Co(en)_{3}]^{3+}$ is lower than that of $[CoF_{6}]^{3-}$.
$(d)$ If the $\Delta_{0}$ for an octahedral complex of $Co(III)$ is $18,000 \ cm^{-1}$,the $\Delta_{t}$ for its tetrahedral complex with the same ligand will be $16,000 \ cm^{-1}$.

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 $(2)$.

The correct option$(s)$ regarding the complex $[Co(en)(NH_3)_3(H_2O)]^{3+}$ $(en = H_2NCH_2CH_2NH_2)$ is (are):
$A$. It has two geometrical isomers
$B$. It will have three geometrical isomers if bidentate 'en' is replaced by two cyanide ligands
$C$. It is paramagnetic
$D$. It absorbs light at longer wavelength as compared to $[Co(en)(NH_3)_4]^{3+}$

Sulphide ions react with sodium nitroprusside in a basic medium giving a coloured solution. In the reaction,the oxidation state of iron: