What is the coordination geometry around the manganese atom in decacarbonyldimanganese$(0)$?

Which of the following statements is not true?

Which of the following is true for the complex $[Fe(CN)_6]^{4-}$?

The number of unpaired electrons in $Ni^{2+}$ (atomic number $= 28$) is ...... .

The geometries of some complex ions are given below. Select the correct answer.
$(1) [Ag(NH_3)_2]^+ - \text{Linear}$
$(2) [MnCl_4]^{2-} - \text{Tetrahedral}$
$(3) [Cu(NH_3)_4]^{2+} - \text{Square planar}$
$(4) [Ni(CN)_4]^{2-} - \text{Square planar}$

Match the correct option.

$A$. $[CoF_6]^{3-}$	$M$. $sp^3d^2$,paramagnetic
$B$. $[Mn(CN)_6]^{3-}$	$N$. $sp^3d^2$,diamagnetic
$C$. $[Co(C_2O_4)_3]^{3-}$	$O$. $d^2sp^3$,paramagnetic
$D$. $[Zn(H_2O)_6]^{2+}$	$P$. $d^2sp^3$,diamagnetic