Which among the following is a correct order of increasing field strength of ligands?

Given below are two statements:
Statement $I$: Among $Zn$,$Mn$,$Sc$ and $Cu$,the energy required to remove the third valence electron is highest for $Zn$ and lowest for $Sc$.
Statement $II$: The correct order of the following complexes in terms of $CFSE$ is $[Co(H_2O)_6]^{2+} < [Co(H_2O)_6]^{3+} < [Co(en)_3]^{3+}$.

Which of the following is a weak field ligand?

For which of the following pairs of complexes is the crystal field splitting energy $\Delta_0$ for $II > \Delta_0$ for $I$?

$I$	$II$
$(a). [Cr(H_2O)_6]^{2+}$	$[Cr(H_2O)_6]^{3+}$
$(b). [Fe(H_2O)_6]^{3+}$	$[Fe(CN)_6]^{3-}$
$(c). [Fe(CN)_6]^{3-}$	$[Ru(CN)_6]^{3-}$
$(d). [NiF_6]^{4-}$	$[NiF_6]^{2-}$

The value of $CFSE$ in a tetrahedral complex having a $3d^4$ configuration of the metal ion,surrounded by strong field ligands,will be:

Which of the following complexes has the highest value of crystal field splitting energy $(\Delta_o)$?